Converting a German targeted Fritz!Box Fon Wlan to an International version


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Hello everybody,

this is my first message to this great forum, and I am sorry it can only be in English as I do not speak German.

Fritz!box Fon Wlan is a wonderful piece of hardware but it is hardly known (and thus distributed) outside Germany.

For this reason, if you live outside Germany, it is quite common to buy this device on e-Bay, and this is what I did.

Unfortunately, chances are that the Fritz!box just cannot work out of the box and a number of interventions are necessary.

This article is intended for helping the non German speaking persons (like me, unfortunately), to have their beloved Fritz working outside of Germany.

This information is based on my understanding of the articles on this forum and hands-on experience in turning my great unusable Fritz!box into a great working Fritz!box.

No need to say that modifying the box voids the manufacturer warranty. Only use these instructions:

- if, after reading these notes, you feel confident with your understanding
- if, as it was my case, you do not see any other use for your unusable box (that is, you have nothing to lose)

This post does not explain anything that is not already explained / found out on this forum. Its only purpose is to expose the subject in english and, possibly, join all the necessary information in one place.

Before I start, I must mention that I asked the manufacturer for information on:

1 whether the box in my possession was ISDN or POTS (analogue)
2 whether it would be possible to convert it from ISDN to POTS
3 whether it would be possible to load an english language firmware on the box

I can post my message and the answer I got if this is of interest to anyone, but basically the answers were:

1 as it is built for the German market, it is ISDN
2 it is impossible to convert it to POTS
3 it is impossible to load a firmware in English

The guy from the support ended making little fun of me concerning point 3 - he said this could be an opportunity for me to improve my German.

Indeed I would love to speak German, to be able to read all the interesting threads of this forum!

After this long introduction, let's come to the technical part of my post.

The first problem to the non German fresh buyer of Fritz on e-Bay is that the box will not synchronise the DSL line.

This is because, as far as I understood, in Germany THE ENTIRE TELEPHONE INFRASTRUCTURE is ISDN!

In the rest of Europe we have POTS as a standard, and when we buy a generic modem it complies with the POTS analogue standard. When we want an ISDN modem, we specify that it has to be ISDN because this is an exception to the rule.

As opposite, in Germany, ISDN is the standard, and it is so normal to have ISDN that many Germans do not even realize that they have ISDN instead of POTS.

Nowhere in my Fritz!Box package (router + packing + manual + stickers) I found an indication of its standard. The web site was of limited help because it just stated that the product is "Annex A" (analog) or "Annex B" (ISDN) depending on the model, but it gave no clue on how to make the distinction. This basic fact gave me the impression that the difference between the "Annex A" and the "Annex B" model had to be in the software.


So how do you get the verdict? If your box does not synchronise, you can check whether it is "Annex A" or "Annex B" using the web interface and checking the picture in "Internet" -> "DSL-Informationen".

On the bottom of the picture you will quite certainly find out that the device is "Annex B" (ISDN) like every piece sold in Germany.

At this point you are probably thinking that you bought the wrong hardware.

OK, this is where we have to forget what the manufacturer says and we have to rely on the friends of the community.

Before we go on, I want to draw your attention on what is inside the tiny red box.

The Fritz!Box is a Linux based device, and as such it provides a set of standard tools to those that are familiar with Unix.

If you have never worked with Linux, you might perhaps ask a Linux enthusiast friend to come and help. He will find this procedure very simple.

The conversion of the Germany targeted box into an international targeted box requires access to the command line.

This is achieved using telnet, that has to be activated using the following sequence on a telephone connected to a "FON" port:


To deactivate telnet:


It is good practice to deactivate telnet when it is not needed.

For the transition from "ANNEX B" to "ANNEX A" it is not necessary to use telnet, but to start getting familiar with the beast I suggest opening a little "explorative" connection, for instance opening a dos box and typing:


or whatever the IP address of your Fritz is.

Once a telnet connection to the box is active, a number of standard Unix commands are available. For instance, the command:


displays the environment variables and is a nice start to check the values of variables like "Country" or "ANNEX".

The transformation from "ANNEX B" to "ANNEX A" is actually a change to the value of one of these variables.

On this forum, there are some nice "scripts" to perform the transition at:

(thank you haveaniceday, I owe you everything!)

Basically, you have to pick the relevant file for you and send it to the router like you would do for a firmware update.

As I am assuming that you bought a German equipment with web interface in German and ISDN (ANNEX B), the right file is:


in the file name, avm stands for the standard german version (as opposed to avme for english language equipment) and "ANNEX A" refers to the effect of running the script, that is setting the equipment to work with analog "ANNEX A" standard.

To install the script, open Fritz! web interface and choose "System" > "Firmware Update"

Click on Browse, pick fritz_als_avm_annex_A_new.tar, press upload.

** IMPORTANT ** The file must be uploaded AS IS, without decompressing it.

You will see the "Info Led" blinking and a message recommending to wait a few minutes on the screen.

At the end of the process the router reboots and you have a router usable with a POTS (analog) line!!

To confirm, open the web interface, "Internet" -> "DSL-Informationen", and you should see that your box is "ANNEX A". If you have the DSL cord plugged, you router has already started synchronising!!

How easy is this? THANK YOU HAVEANICEDAY!!


If you are afraid of harming your Fritz!box now that it is finally usable or you just don't have any interest in changing the language (because you are a german living abroad, for instance), then you can stop reading here.


Still there? Then take a pause, as this is where it gets a bit tougher.

Unfortunately, downloading the English firmware from the manufacturer website is not enough. If you try to install the international (english) firmware, you get an error.

When the firmware is uploaded to the box, there are checks that are performed to make sure the new firmware is appropriate for the box. As your box is German (avm), the English (avme) firmware installation fails.

To overcome this problem, you have to make very few changes to the firmware.

The firmware comes as a standard tar file, and with any flavor of Unix it can be expanded, modified and compacted again.

As soon as the firmware is sent to the box, a script is run to perform some checks and eventually install the firmware. We need to slightly change this script.

Untar the firmware in a directory, i.e. patch:

mkdir patch
cd patch
tar xvf ../firmware.image

you get a ./var directory containing, among other stuff, a script called "install"

edit the script:

vi ./var/install

and locate the platform check. Where the script checks for the string "avme" (in the list of accepted installtypes) modify "avme" in "avm", so that the script will go on if the OEM string found is "avm" (what you have).

There are two such checks, one for "Annex A" and one for "Annex B". To be on the safe side, just modify both occurrences of
"avme" in "avm".

When the install script is patched, just create the tar file again:
cd patch
tar cvf patched.image ./var

and check that the newly created tar file has the same structure than the original one. More specifically, make sure that the contents of the tar file start with a trailing slash:

tar tvf patched.image

The file should have its contents with the relative path ./var/ and not just var or /var. (Actually I am not sure about the importance of this detail, but the original firmware features the ./).

The "patched" firmware image is ready to be uploaded to the box using the web interface.

*** IMPORTANT - Please read further on before actually uploading the patched image ***

The sending of the patched image should work like a charm, but when the router will reboot.... it will not be the end of the story.

Please do not panic when you will notice that the web interface is not working anymore. It is just part of the job, and there is an explanation for everything.

To solve and understand the problem we have to connect using telnet (see above).

With an established telnet connection, go to the var directory on the Fritz!Box:

cd /var
ls -l

you will see that there is a link called “html” pointing to /usr/www/avm/en

This link points to a non coherent (and non existing) hybrid, as we learned by now that "avm" stands for the German version and "en" stands for English...

To repair the web interface we just rename this defective link and we create the correct one:

mv html html.orig
ln -s /usr/www/avme/en html

Then we restart the webserver:

killall websrv

and voilà, the English web interface is alive, as you can check with your browser.

At this time, the best use we can make of the web interface is to upload another great contribution from HAVEANICEDAY: the script:


again from:

and, if at the consequent reboot we still lack the web interface, we manually correct the html link and restart the webserver as explained above.

The final step is uploading the english firmware as downloaded from the manufacturer web site to the box, so that we make sure that everything is as it should be.

This is all: after following these instructions, your box should be as great and useful as mine.

Just a few final words. When I modified my Fritz!Box Fon Wlan I was working in "nothing to lose" mode. I did not take any notes, this is why I tried here to pass the idea more than the specific commands.

I decided to spend a few hours of my time writing this paper hoping that someone I don’t know could find it useful because I believe in the sharing of the information. I "recycled" a box that was of no possible use to me thanks to the posts I found on this forum, and I wanted to make the information accessible to the English speaking.

I was very disappointed by the manufacturer answer to my questions. Fritz!Box Fon Wlan is a fantastic product, deeply based on open source solutions. In embedding open source software in their commercial products for profit, I think the manufacturers should also commit to "openness" to their customers. After all, if I threw my Fritz!Box Fon Wlan in a trash bin (as they almost suggested), it would have certainly not been to buy another one.

Please do not hesitate to send your feedback, corrections and opinions.


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Thank you very much, great article.
Hi Opensoft,

I like to add some information.

Not everybody at germany does have ISDN. I have still POTS...
But... all provider at germany use Annex B for DSL. But I am just 99.999 sure ;-)

POTS + Annex A DSL => works
ISDN + Annex A DSL => conflict in frequence ranges !
POTS + Annex B DSL => works
ISDN + Annex B DSL => works

The advantage of using only Annex B is having a unique hardware.
Unfortunately "loong" lines with POTS might get a higher transfer rate with Annex A.

The hardware for Fritz "Annex A" and Annex B" is different ! The frequency
adapter is different.

It's possible, if the firmware supports, to tell a Fritzbox with Annex B frequency adapter to try an Annex A connection.
But only if the DSL-firmware supports. A 7170 might not.. ( never seen a successful try ).
Also "ADSL2+ Annex B" firmware might not try/support Annex A always and
this might become worse in the future.

For sure the Annex B hardware will have trouble with "bad long Annex A" lines.
Also the firmware does not support all kind of possible DSL negotiation of protocols.

AVM just to supports "proper" configuration. AVM can not guarantee the Annex A

International interface:
It's critical to set a box from the german web interface to the international web-interface.
The firmware checks "HW revisions", see this thread for a picture.

The german version provides the web interface from here:
Provider can be avm, 1und1,freenet,tcom, ... but never avme

The international version gets it from :

The box does not come proper if you have wrong settings of provider and/or language.
The boot procedure is not prepared to work without web a proper setting.
I have never a deeper look at this to find a secure way to do a international/german switch.
But I know several people asked for help, cause they messed up the box
with wrong settings.

Best regards,

Thank you haveaniceday,

you gave us (the sad non german speaking folks) a lot of information. If you say that the hardware is not the same, I believe you!

My attitude towards the manufacturer was a bit rude because while waiting for their official answer I had already managed to have the box working in ANNEX A, thanks to your script! I read their message saying " is impossible..." while your script already proved that it actually can be possible.

However, I am very satisfact with the product now. It has been online non stop for several days and I believe that it will do well in the future.

My ISP has ADSL 2+ and offers speeds up to 16 Mb. I do not have that much bandwith, but as soon as a friend of mine will have his 16 Mb line installed I will test my Fritz "Artikel 2000 1666" at his place to see if it gets the full throttle.

You said that the 7170 is not yet known to accept ANNEX A. What is the situation with other models like the 7050?

I know that all this information has already been debated on the forum, but, believe me, it is a pain to try to understand German solely relying on Google Translate!

Thank you again for your precious information!

Greeting from Lisbon,

opensoft schrieb:
You said that the 7170 is not yet known to accept ANNEX A. What is the situation with other models like the 7050?

I just know about problems with the 7170. The firmware is overwriting any
setting with Annex B and does not respect the environment variable. It's also
bad for the 7170, cause there is no official support for the "ATA" Analogue
Telephone Adapter.

This ata mode can be used on 7050/Fon WLAN,... to dedicate one port as
connection to any Internet router to provide VoIP.
So this is still a nice way to use some of the fritzboxes behind the regular local DSL modem.
( No problem with Annex A/B, long line, internal Fritz DSL modem problems )
All boxes with 2 Lan interface support (?). Check the HW Revision picture and
the "ATA" feature.

Unfortunately the 7170 does not support. ( 4 Lan connectors, but they are just
one internal linux eth-interface with a four port switch. )
AVM release inbetween a 7170 software which was aware of this, but this was
an internal AVM mistake and 29.04.01 does not support this any more.
( technical background: other devices connected to the 4-port switch might
claim the DHCP-internet address, 7170 can not avoid... )



PS: Oops, during I wrote this:
Somebody had trouble with a 7050 and 14.04.01 to set to Annex A. He had
to switch back to an older firmware version.
So sometimes in the near future it might be required to modify the whole
firmware to get Annex A on a regular Annex B box... ( implant Annex DSL-firmware
part ).
Unfortunately the 7170 does not support. ( 4 Lan connectors, but they are just one internal linux eth-interface with a four port switch. )

I see, if I understand this means that, unlike the 7170, the 7050 can act as an ATA adapter and as an IP router, because you can have different IP addresses on the two ethernet ports. Interesting... although it would be a pity to waste a 7050 to act as an ATA. In any case, it would still be better than a common ATA because it allows for using one phone (analog or ISDN) to manage fixed line + up to ten VoIP subscriptions!

But would I loose the traffic shaping feature in such environment? Perhaps not, it could depend by the firmware... or you could have an external router respecting TOS flags... mumble... ...mumble

Perhaps we are going a bit out of topic, but I am so glad to discuss this stuff in english with a Fritz guru ;)

I am learning a lot with your help! Thank you!

Um abraço,

opensoft schrieb:
But would I loose the traffic shaping feature in such environment? Perhaps not, it could depend by the firmware... or you could have an external router respecting TOS flags... mumble... ...mumble
Yes, traffic shaping and TOS is lost. But VoIP works fine. That should be enough for most of the user.
But a current 7050 should work fine with the right firmware...

With with more complex firmware modifikation it should be possible to have ATA and Annex A.
But we need somebody interested in Annex A, little developer know how and some
Linux understanding to realize.

Best regards,

English firmware?

Great minds, great ideas ...
Thank you for the information I have been looking for.
I also have the Fritz!Box Fon Wlan 7050 - German - Annex B and I want to have
the English Web interface. I am ready to try, but... where can I find the english/
international firmware (ver. 14.xx.xx) ?

You are right geonolis,

I might have dreamt, but I am quite sure it was available for download on the manufacturer web site.

Indeed I have noticed some changes, I am wondering if they removed the 7050 english support files :confused:

In any case, the place where they should be is:

Does anybody know about the english 14.04.01?


Hi roi091,

the problem is that there are no downloads associated to the 7050, and I have the feeling that in that same page there was a 7050 choice some days ago.

But perhaps I really dreamt about it.... I am just surprised that there is no download for the international 7050 at all, not even a previous release of the firmware.

The 7050 is considered a new product in the english language site, therefore I was wondering if all international 7050 came with the 14.04.01 already installed, which could justify the lack of the "firmware update" on the site.

Is there anybody owning an international version of the 7050 that can check the firmware version on their box?

In any case, browsing the ftp tree, I have seen that the manufacturer is working at a beta release of the german firmware that will support one of the few missing features of the product: the WDS.

WDS allows several access points to collaborate for expanding the wlan range!



opensoft schrieb:
Hi roi091,
... there is no download for the international 7050 at all, not even a previous release of the firmware.
Is there anybody owning an international version of the 7050 that can check the firmware version on their box?
First of all, let us make clear that there are english/international firmwares with version numbers earlier than 14.04.01 (example: 14.03.91).

Searching on the net I have found this:
Um das Branding auf 'AVME' ändern zu können (um z. B. internationale Firmwares zu installieren), muss wahrscheinlich zunächst ein Downgrade auf eine alte Firmware durchgeführt werden, die sowohl das deutsche als auch das englische Webinterface beinhaltet. Für die Fritz!Box Fon WLAN z. B. sind in der Firmware 08.03.37 beide Webinterfaces enthalten.
That is: "In order to change the branding to 'AVME' and be able to install international firmwares, downgrade first to an old firmware, where both the German and the English Web interface are contained. For the Fritz!Box Fon WLAN e.g. in the firmware 08.03.37 both Web interfaces are contained." !
So, possibly we do not need to find any "english" firmware BUT if we can find an older German firmware for 7050 (e.g. 14.03.37 ?) and we change the branding:
echo "firmware_version avme" > /proc/avalanche/env
exit 1

then the web interface will point to (according to where the link: /var/html links to) the english html directory at:
if this directory exists in the setup - it does not exist at 14.04.01.
Of course, we shall have to comply with an older firmware - with english web interface :) .
Waiting for your opinions and new ideas,
Zuletzt bearbeitet:
Hi geonolis,

unfortunately I do not own (yet) a 7050, but I am trying to get one and of course as soon as I get it I would like to adapt it to my needs which appear to be the same as yours.

By the way, have you found an older release of the firmware to download?

I could not find any release on the net, but someone must have it on this forum, in case we could ask. The problem is I do not speak German!

Let's keep this thread alive and I am sure that we will find our way!

I have never seen an english version of the 7050.
The Fon WLAN or other images from
contain just a part of the interface required for the 7050.


PS: A modifikation should be possible for a Fon WLAN. I will have a look at it.
Hi haveaniceday,

thank you for your interest.

My FBF WLAN (2000 1666) is already fully converted to English Annex A, apart from the possible limitations I can expect for higher speeds that we already discussed.

The strange thing about the 7050 is that although it is commercialised in the international version (at least I assume so because, unlike the 7140 and 7170, it is in the english pages of avm site) there are no downloads associated.

Do you have an image for any English,or both German and English, firmware release? Considering what geonolis is saying, even a release older than 14.04.01 could do.

Thank you!

Hello geonolis,

thanks to haveaniceday ;) I discovered an Italian forum ( that confirms your procedure on changing the language by downgrading to an older version and updating again.

It seems just a matter of finding a firmware for the 7050 old enough to have both German and English and it can be done.


opensoft (who, by the way, happens to be Italian :rolleyes: )
So nothing to do for me.

So nothing to do for me.


I would not say that haveaniceday!:eek:

We always need your help! Do you know of a place where we can download a valid firmware for 7050, for instance? I am Italian and without your answer to another Italian guy I would not know :blonk:

The italian forum points to a voip provider where you can download old versions of firmware for several FBF models, but the 7050 is not included :heul:

Ciao da Lisbona,

Here in the forum you can use the ds-mod (danisahne) to unpack the language module from 08.04.01 english firmware, download the german (7050) 14.04.01 and unpack it too. Replace the german (7050) language module with the english one and voila, you've converted the german 7050 to the english (7050) firmware. It works for me.
quoting voipmustbe

Here in the forum you can use the ds-mod (danisahne) to unpack the language module from 08.04.01 english firmware, download the german (7050) 14.04.01 and unpack it too. Replace the german (7050) language module with the english one and voila, you've converted the german 7050 to the english (7050) firmware. It works for me.

This is great news! If I only could read German! :blonk:

If I understand, 08 versions are for the "simple" WLAN and 14 versions are specific for the 7050. But does the web interface for the WLAN fit for the characteristics of a 7050? I (perhaps wrongly) assumed that a 7050 would have more things to setup, i.e. three "fon" ports instead of two. :confused:

When you say it works for you, do you mean "I do not need the 7050 specific settings"? :confused:

Thank you,

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