vous pouvez tenter ce process, meme si l'erreur n'est pas explicite d'un environnement provider... ca peux aider...
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. Download the recovery tool for your Fritzbox. This can be found on the AVM FTP server
ftp://ftp.avm.de/fritz.box/. Once on the AVM FTP you will need to navigate to the directory that relates to your fritzbox. Now navigate to the x_misc folder. Next select the correct folder for your language. Finally you need to download the executable namedFRITZ*.recover-image.exe where the * is the model of your Fritzbox, languages and firmware version, download and save this file
Connect an Ethernet from LAN1 on the Fritzbox to your PC directly. Disconnect all other network cables from the Fritzbox.
2. Run the recovery tool on a Windows 7/8/10 machine (NOTE: do NOT run as administrator), and follow the instructions. You'll need to power-off the device, select the NIC on your PC that you connected to, and then power the device back on.
3. After the recovery tools starts talking to the device it will establish an IP address and check the software version. Then you will get to the point where it complains about the settings being set by a service provider.
4. At this open, open a Command Prompt, and type the command: "ftp <IP address>" replacing the IP address with the one shown in the recovery tool.
You will connect to the ADAM2 boot loader ftp server. Login with the username "adam2" and password "adam2".
5. At the ftp prompt run the command: "quote UNSETENV provider". It will respond with a successful confirmation. Then type "quit" and close the command prompt.
Now you can close the Fritzbox recovery tool. Then open the recovery tool, again following the instructions. This time you should not be presented with an error about the provider and the tool should flash the Fritzbox.
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