License activation problems When the installer cannot activate your license it says which kind of problem it met. Each kind has its own fix.
A payment went through but the invoice is still unpaid The customer paid at the provider and the invoice still says Unpaid. Almost always, the provider's callback never reached WBAMS.
Troubleshooting: where to look first Most problems announce their cause in a log. Reproduce precisely, read the logs, then change the smallest thing.