NpgSQL error "FATAL: 28000" in using postgreSQL through .NET -

NpgSQL error "FATAL: 28000" in using postgreSQL through .NET -

until today uses postgresql through (vb) .net. don't know how may cause in ide can't open form's designer within project anymore. instead of opening error page appear message:

fatal: 28000: no postgresql user name specified in startup packet.

if run project behaves ok including postgresql functions.

did faces , should wanted functionality , able edit designers mouse?

windows 7, postgresql 9.3

.net postgresql npgsql