A year later... 🙂

The following fixed it in my case. Change the reg entry TypeGuessRows to 0

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

"win32"="C:\\WINDOWS\\system32\\msexcl40.dll"

"DisabledExtensions"="!xls"

"ImportMixedTypes"="Text"

"FirstRowHasNames"=hex:01

"AppendBlankRows"=dword:00000001

"TypeGuessRows"=dword:00000000