Payment Configuration text not working

[jonso100]

Hi
First post so hope I'm in the correct section:

VM 2.0.24, upgraded from V1.

Long story short - upgraded from V1 to V2 ages ago (which seemed to go OK, site still worked!) on a site which was being used as a catalogue only. Now want to sell things, and when I enable PayPal as a payment method, under the configuration setting all the text is e.g. VMPAYMENT_PAYPAL_LOGOS i.e. it's not picking up the language files. The language files are there though in both administrator/language/en-GB/ and language/en-GB/.
It's not just paypal, all payment methods do the same thing.
PayPal actually works though, although in the emails generated I get VMPAYMENT_ and other examples where the language isn't being picked up.

I've manually downloaded the 2.0.24 files, removed what was on the server and replaced with those and updated the db tables via Tools > Tools & Migration.

Any one have an idea what's up/what I need to do to fix?

many thanks
Jon

[GJC Web Design]

Updated the AOI?
What doew Joomla language debug say?