The most common error in web screens appears during login. 

This error is an Unexpected error:

An unexpected problem has occurred. Please try again or contact your administrator for assistance.

What to look for:

1.  Check <Sage Programs>\Online\Web\Logs\trace.log
   1. This debug file is populated with errors during startup and login. Note the timestamp is GMT time
   2. Each section will give some feedback to what is occurring.
2. Check <Sage Programs>\Online\webapi\logs\trace.log
   1. This trace file would be for webapi connections

• Most errors are related to connection to database,
  • Usually a HRESULT error message. (Portal database is not connecting or defined)
  • mscorlib error not could not find dbconfig.xml
  • The remote certificate is invalid according to validation procedure (DSN is not connecting on web server.