JET and ODBC driver missing, can not get data from MDBs

Question

These are MY symptoms: (XP Pro, 32bit)
-Programs that access .mdb databases (aside from Access 2007 itself) can not get any data.
-Using the Data Sources in Visual Studio 2008 to connect to an MDB shows tables, but you can not query. you receive "Unknown Error" from the Microsoft JET Database Engine
-ArcCatalog can not read a personal geodatabase (mdb), after opening the database it has no feature classes within it
-Trying to bring up the properties of a User DSN "MS Access Database" in the ODBC Data Source Administrator returns error
"The setup routines for the Microsoft Access Driver (*.mdb, *.accdb) ODBC driver could not be found. Please reinstall the driver."

I attempted to reinstall latest MDAC (by setting it to compatibility mode of windows 2000) and latest JET driver. Reinstalled XP SP3.
Also tried a lot of regsvr32 gymnastics with the dao350.dll and dao360.dll, uninstalled the dao350, etc, etc. Nothing worked.

Answer 1

(Yes, I'm answering my own question, to record my solution)

I should also note, in addition to above, I couldn't use the SQL Native Client driver either.

In the registry, under HKLM\SOFTWARE\ODBC the \ODBC.INI branch contains any defined connections, and the \ODBCINST.INI contains records for the installed drivers.

I checked a similar development machine, and my ODBCINST.INI was missing A LOT of entries. I blame the ccleaner application that was recently used to clean up my system of junk.

After exporting the registry branch from the other computer, and importing over my existing keys, everything worked again.

Below are some of the core records, to generate a .reg script. You should get the full list from a similar machine to yours.

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SOFTWARE\ODBC\ODBCINST.INI]

[HKEY_LOCAL_MACHINE\SOFTWARE\ODBC\ODBCINST.INI\Microsoft Access Driver (*.mdb)]
"UsageCount"=dword:00000002
"Driver"="C:\\WINDOWS\\system32\\odbcjt32.dll"
"Setup"="C:\\WINDOWS\\system32\\odbcjt32.dll"
"APILevel"="1"
"ConnectFunctions"="YYN"
"DriverODBCVer"="02.50"
"FileUsage"="2"
"FileExtns"="*.mdb"
"SQLLevel"="0"

[HKEY_LOCAL_MACHINE\SOFTWARE\ODBC\ODBCINST.INI\Microsoft Access Driver (*.mdb, *.accdb)]
"UsageCount"=dword:00000003
"Driver"="C:\\PROGRA~1\\COMMON~1\\MICROS~1\\OFFICE12\\ACEODBC.DLL"
"Setup"="C:\\PROGRA~1\\COMMON~1\\MICROS~1\\OFFICE12\\ACEODBC.DLL"
"APILevel"="1"
"ConnectFunctions"="YYN"
"DriverODBCVer"="02.50"
"FileUsage"="2"
"FileExtns"="*.mdb,*.accdb"
"SQLLevel"="0"

[HKEY_LOCAL_MACHINE\SOFTWARE\ODBC\ODBCINST.INI\Microsoft Excel Driver (*.xls)]
"UsageCount"=dword:00000002
"Driver"="C:\\WINDOWS\\system32\\odbcjt32.dll"
"Setup"="C:\\WINDOWS\\system32\\odexl32.dll"
"APILevel"="1"
"ConnectFunctions"="YYN"
"DriverODBCVer"="02.50"
"FileUsage"="1"
"FileExtns"="*.xls"
"SQLLevel"="0"

[HKEY_LOCAL_MACHINE\SOFTWARE\ODBC\ODBCINST.INI\Microsoft Excel Driver (*.xls, *.xlsx, *.xlsm, *.xlsb)]
"UsageCount"=dword:00000003
"Driver"="C:\\PROGRA~1\\COMMON~1\\MICROS~1\\OFFICE12\\ACEODBC.DLL"
"Setup"="C:\\PROGRA~1\\COMMON~1\\MICROS~1\\OFFICE12\\ACEODEXL.DLL"
"APILevel"="1"
"ConnectFunctions"="YYN"
"DriverODBCVer"="02.50"
"FileUsage"="2"
"FileExtns"="*.xls,*.xlsx, *.xlsb"
"SQLLevel"="0"

[HKEY_LOCAL_MACHINE\SOFTWARE\ODBC\ODBCINST.INI\SQL Native Client]
"UsageCount"=dword:00000001
"Driver"="c:\\WINDOWS\\system32\\sqlncli.dll"
"Setup"="c:\\WINDOWS\\system32\\sqlncli.dll"
"APILevel"="2"
"ConnectFunctions"="YYY"
"CPTimeout"="60"
"DriverODBCVer"="09.00"
"FileUsage"="0"
"SQLLevel"="1"

[HKEY_LOCAL_MACHINE\SOFTWARE\ODBC\ODBCINST.INI\SQL Server]
"UsageCount"=dword:00000002
"Driver"="C:\\WINDOWS\\system32\\SQLSRV32.dll"
"Setup"="C:\\WINDOWS\\system32\\sqlsrv32.dll"
"SQLLevel"="1"
"FileUsage"="0"
"DriverODBCVer"="03.50"
"ConnectFunctions"="YYY"
"APILevel"="2"
"CPTimeout"="60"