The requested Payment Method is not available

[pinkdigital]

Following an upgrade to 1.9.2 our customer is not able to open orders placed before the update in the Admin system. Has anybody else experienced this? The error is "The request Payment Method is not available". This part of the system hasn't changed from Paypal.

[magebay]

We have got same problem when customer report that they can not view order to get invoice.

However, the problem on Magento ver. 1.8.1.0.