UPDATE 22/05/2012: a new firmware is available for the Vodafone Huawei HG556a router.
Please note! If you have made changes to the default settings for the Wireless, LAN, FTP or Print Server parameters etc. then you should take note of these changes before upgrading the firmware and then manually re-apply them after you have restored the default settings.
To update the firmware for your Vodafone Huawei HG556a please follow the instructions below:
1. Click here to download the latest firmware file . On the popup dialog box click Save and set the storage location of the ZIP file. Extract the BIN file to a convenient location such as your desktop; you will need to locate this file later on.
2. Start your Internet Browser and type the following IP address http://192.168.1.1 into the address bar and press Enter on your keyboard.
3 . When prompted, use the following details to log into the advanced configuration utility:
User name: advanced
If the login details above do not work then your router may be using an old firmware version so try the following instead:
User name: admin
4. The configuration page will open as shown in the attached screenshot below.
From the left hand menu select Management then Update Software.
Click for screen shot .
5. Click on the Browse... button, locate the BIN2 file you extracted earlier from the ZIP file and click Open.
6. Click the Update Software button.
Do NOT power off your router while the software update is in progress!
7. After the firmware upgrade process had completed it is recommended that you restore the default settings of the router.
8. From the left hand menu select Management > Settings > Restore Default
Alternatively you can physically reset the router by pressing and holding the Reset button on the rear panel of the router for five seconds.
9. Click the Restore Default Settings button and click OK when prompted.
10. Close the configuration utility webpage and wait for two minutes while the router reboots.
I have tried the up-date posted by Paul F for the Vodafone Huawei HG556a router but when I downloaded the zipped file its file extension was .bin not .bin2. Tried to upload this file but got an error message saying 'Fatal error during image uploading' and the modem did not up-date.