Can't start BDEADMIN 5.0, DBEXPLOR

After starting BdeAdmin I receive following Errormessages. The same
messages I receive after starting DbExplor, or by using TTable.Database,
TDatabase.Alias, TTable.TablenName

BDE Error: Object not found [$22] [$8]

Reinstalling Delphi 4 and BDE doesn't resolve the problems!

Who can help?

Thanks
Hans Normann