Issue resolved
Issue:
We have been having a problem yesterday and today where callbacks from PayPal Standard/Express and Barclays ePDQ have been failing.
This issue is now resolved.
Techy-talk:
The actual problem was due to those PSP's sending the callbacks with a blank user-agent string.
This was causing .NET to throw an exception whenever the request object was used to access the user-agent string.
This should never happen anyway as the variable being referenced was defined as string but I guess MS had other ideas.
We have now put additional validation in place to check for this eventuality and it should not happen again.
