Some added toolbar and anti-virus add-ons are known to cause Firefox issues. Disable All of them.

Many site issues can be caused by corrupt cookies or cache.

• Clear the Cache and

• Remove Cookies Warning ! ! This will log you out of sites you're logged in to.

Type about:preferences<Enter> in the address bar.

• Cookies; Select Privacy. Under History, select Firefox will Use Custom Settings. Press the button on the right side called Show Cookies. Use the search bar to look for the site. Note; There may be more than one entry. Remove All of them.
• Cache; Select Advanced > Network. Across from Cached Web Content, Press Clear Now.

If there is still a problem, Start Firefox in Safe Mode {web link} While you are in safe mode;

Type about:preferences#advanced<Enter> in the address bar.

Under Advanced, Select General. Look for and turn off Use Hardware Acceleration.

Poke around safe web sites. Are there any problems?

Then restart.

When I restarted Firefox in safe mode it worked. I looked for Use Hardware Acceleration but couldn't find it. I also checked cookies and the site wasn't in there also I cleared the cache. When I restarted Firefox in normal mode I still had the same problem. What should I look at next?

Please check this picture.

Thanks for that, I have unchecked the Hardware Acceleration but the login button still doesn't become active in my normal mode. How do I find out what is stopping this happening as it works in safe mode?

Type about:addons<Enter> in the address bar to open your Add-ons Manager. Hot key; <Control>(Mac:<Command>)<Shift> A)

In the Add-ons Manager, on the left, select Extensions. Disable a few add-ons, then Restart Firefox.

Some added toolbar and anti-virus add-ons are known to cause Firefox issues. Disable All of them.

If the problem continues, disable some more (restarting FF). Continue until the problem is gone. After, you know what group is causing the issue. Re-enable the last group ONE AT A TIME (restarting FF) until the problem returns.

Once you think you found the problem, disable that and re-enable all the others, then restart again. Let us know who the suspect is detective.

I have noticed now that if I enter the password manually then the logiin button becomes activated but if I fill it remotely with my Roboform program it doesn't. However I am now able to login but don't know why British Gas needs it to be manually entered whereas other web sites don't.

Hmm. Some web sites don't like auto-fill i guess. Next time, wait for the auto-fill to work, then add a space to the end of the user name, then delete the space.