I can log into my Avast account here, using my password, but when I go to change my password on this website, it tells me my existing password is entered incorrectly (but this is the password I used to log in here).
Similarly, on my pc, Avast is installed and works fine but if I wish to change settings, it rejects the password I use (same as for logging into avast.com).
Can you help?
thanks, Bill
I hae the same problem. Help me 
I’m not entirely clear what it is you are trying to achieve, so I have expanded on three areas that it could be.
The password on the forums is directly related to your my.avast.com account settings. When you log in on this forum your credentials are checked against your my.avast.com account.
So you would ultimately have to change the password for your my.avast.com account.
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The installation of avast on your PC is totally different, it bears no resemblance to either the my.avast.com of forum password. By default there is no password set to protect your avast program settings; if you have forgotten the password for that or didn’t set a password to protect your avast program settings (it could mean some corruption of your installation).
A clean reinstall of avast is your best option, you probably won’t be able to uninstall avast (because of the password issue) and will have to use the avast uninstall utility.
Download the avast! Uninstall Utility, avastclear.exe http://files.avast.com/iavs9x/avastclear.exe and save it to your HDD.
Download the avast version and save to your HDD so you don’t have to go online without protection after you run the uninstall utility:
You don’t say what version of avast you are using so I have given a direct link to download the free version:
Free AV: - http://files.avast.com/iavs9x/avast_free_antivirus_setup.exe
Now run the avast! Uninstall Utility, it will request it be run from safe mode (and will handle the boot into safe mode), once complete reboot into normal mode.
Install the latest version, reboot.
I do not see why this has to be so difficult.
I can login to the Forum using my Facebook account.
When I subscribed to Avast, I received an email including an automatically generated password.
I logged in to the Forum and Chrome saved the password for me. This confirms that the password used is the same as the one in the email.
However, if I try to login manually using this exact password, it is not accepted. If I copy and paste this password into the ‘Change Password’ option it says the password is incorrect.
So how did I login using that password?
How am I supposed to change it?
NOTE - This has nothing to do with the Application on my PC - only the Website.
Had I known this sort of thing was going to happen I might well have chosen a different AV product, as this is not very reassuring.