Im not sure if this'll do the trick, because i have never had this problem, but i got this off of a website:
Microsoft OLE DB Provider for ODBC Drivers (0x80004005)
[Microsoft][ODBC Microsoft Access Driver]General error Unable to open registry key 'Temporary (volatile) Jet DSN for process 0x500 Thread 0x594 DBC 0x13c8024 Jet'.
includes/setup.asp, line 20
This message usually means there is a problem with your setup.asp file, or the location of your database file (For example, the pdshoppro.mdb file may be missing).
First, check the configuration in your setup.asp file. Make sure your path or DSN to the database is correct. You also should make sure you have the latest MDAC drivers installed. Also, if you have tried to open the database using MSAccess, and now get this error you may need to restart the IIS service.