I have a customized theme and tried to upgrade my forum to v1.6 today. When I go to log in, the check box which used to show the "Remember Me" message next to it now shows "undefined".
Could anybody help me and advise me on how to fix it so it shows the right line again?
You'll need to revert all your templates to default after the upgrade. If it's saying this then something's not been updated properly or reverted to default.
How do I revert to default? Will I risk losing some of the customizations by doing that (I had the theme customized about 2 years ago).
You're going to have to revert a fair few templates to default, 1.6 features either aren't going to be showing on your board, or will be broken. You can't use a 2 year old theme on a new feature release when new things are added. To see what needs reverting, go to ACP > Templates & Style > Templates > Find Updated Templates > for each one go Options > Revert to Original, or click Diff Report to see what's actually changed.
I've done some reading and messing around in the meantime and may have solved this one (at least so it seems at this point). I've ended up adding the following to the header_welcomeblock_guest template and it appears to have solved my problem.
lang.remember_me = "{$lang->remember_me}";