PROBLEM
There is a problem in which Microsoft Excel 2007 .xlsx files cannot be seen in ArcCatalog or in the ArcMap Add Data dialog box, even though a valid Excel 2007 spreadsheet exists and is a supported ArcGIS Desktop input format.
The file GxObjFactCache.dat is corrupted. This file is located at:
C:\Documents and Settings\<user>\Application Data\ESRI\ArcCatalog\GxObjFactCache.dat
For more recent versions of ArcMap, it is found in:
C:/Users<username>/AppData/Roaming/ESRI/Desktop10.X/ArcCatalog/GxObjFactCache.dat
Delete the corrupted file (GxObjFactCache.dat) located at:
C:\Documents and Settings\<user>\Application Data\ESRI\ArcCatalog\GxObjFactCache.dat
When ArcCatalog or the Add Data dialog box in ArcMap are accessed again, the file is regenerated.
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