There was a problem with payment integrations introduced last night which is now resolved.
The issue was caused by a change the the URL handling we made to enhance SEO and Analytics (see release announcement 11 hours ago!)
URLs are, in theory, case sensitive, although in practice we don’t care.
http://www.starkadder.org.uk/Sales/Genres/Cinema/T2TRAINSPOTTING218
and
http://www.starkadder.org.uk/sales/genres/cinema/t2trainspotting218
both go to the same place, but will show up separately on Google Analytics. We added a change so that if you go to a URL with a capital letter in it, it would automatically redirect you to the lowercase version. This way, all hits on the same page would be counted in the same place.
Unfortunately, this had an impact on some payment integrations. When affected payment integrations complete a transaction, they connect to a URL to tell us the payment has been received. The notification URL they connect to had capital letters in it, so they were getting the redirect, and instead of following the redirect, they just stop processing. Not all payment gateways work this way, and not all payment gateways ignore the redirect, which is why we didn’t notice earlier.
We’ll be checking all the transaction logs, correcting problems where we can, and following up to individual customers with lists of transaction which had problems shortly.