Hi Pat,
It is best to contact Tech Support for help on this if you still have issues after trying the ideas below.
If your install is a old install (not 5.5 SP2 - 5.5.597.0) then make sure to you install SP2. Check this -
Manual Update to SP2 - D-Tools Documentation Wiki
The SP2 Server install will install a SQL Instance which is compatible with both 32 and 64 bit OS. Before running this install make sure to uninstall any SQL instances you do not need and also the uninstall the D-Tools server and client.