the answer to my registry question is:

To change the value of TypeGuessRows, use these steps: 1.On the Start menu, click Run. In the Run dialog box, type Regedt32, and then click OK.

2.Open the following key in the Registry editor:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Jet\4.0\Engines\Excel

Note For 64-bit systems, the corresponding key is as follows:

HKLM\SOFTWARE\wow6432node\microsoft\jet\4.0\engines\excel <---except this should be: HKEY_CLASSES_ROOT/wow6432Node/Microsoft/Jet/4.0/engines/

3.Double-click TypeGuessRows.

4.In the DWORD editor dialog box, click Decimal under Base. Type a value between 0 and 16, inclusive, for Value data.

5.Click OK, and then exit the Registry Editor.