Error message, Please help

Ive had PT3 working fine previously, 2 days ago I got AK HUD to work with is also, this worked great for 2 days and then when I turned it on today I got this message and cant fix it.
"Unable to log into database (PT3_2008_03_01_215546). Reason: could not connect to server: Connection refused (0x00027D/10061) Is the server running on host "localhost" and accepting TCP/IP connections on port 5432?"
I havent changed anything since it worked fine but my PC crashed towards the end of yesterday and I didnt switch it back on. Could this have corrupted something? If so what should I check?
"Unable to log into database (PT3_2008_03_01_215546). Reason: could not connect to server: Connection refused (0x00027D/10061) Is the server running on host "localhost" and accepting TCP/IP connections on port 5432?"
I havent changed anything since it worked fine but my PC crashed towards the end of yesterday and I didnt switch it back on. Could this have corrupted something? If so what should I check?