Unable to log in from XP to Windows 2008 R2 RDS

If you have enabled the network authentication in windows XP SP3 yet you still can't connect (Error 0x80090303) it could be you are using an IP address or Alias for the TS/RDS server.

There is a bug in the SP3 routines that means only the server name will work.

To get around this use the following hotfix(es)...

Using Windows XP Remote Desktop with Windows 2008r2 RDS

If you get an error saying "Network Level Authentication" is required see the following MS artical...

http://support.microsoft.com/kb/951608

32bit Application using ODBC on Windows 2008 r2 64

If you are having problems with your application connecting (even though the odbc entry says it connects fine) it could be you need to add a 32bit ODBC entry as the one the system created using the normal tools is a 64bit ODBC driver.

To do this use the following program (remember to remove the 64 bit entry first!)...

%SystemRoot%\SysWOW64\ODBCad.exe    (normally c:\Windows\SysWOW64\ODBCad.exe)

There are numerous 32bit routines (such as regedit) that work on the 32bit area of the registry.