I have exactly the same problem as discussed in thread195-107703. In addition I tried inserting ThreadingModel key into the InprocServer32 node and tried all possible values. I verified that the DLL loads in-process and I examined my entries through OLE Viewer. I see no errors.
The below is my registration file.
Windows Registry Editor Version 5.00
[HKEY_CLASSES_ROOT\pfeControlShell.CoControlShell]
[HKEY_CLASSES_ROOT\pfeControlShell.CoControlShell\CLSID]
@="{40B2858F-856F-4618-90DF-B42349E0A0FF}"
[HKEY_CLASSES_ROOT\CLSID\{40B2858F-856F-4618-90DF-B42349E0A0FF}]
@="pfeControlShell.CoControlShell"
"AppID"="{40B2858F-856F-4618-90DF-B42349E0A0FF}"
[HKEY_CLASSES_ROOT\CLSID\{40B2858F-856F-4618-90DF-B42349E0A0FF}\AppID]
@="{40B2858F-856F-4618-90DF-B42349E0A0FF}"
[HKEY_CLASSES_ROOT\CLSID\{40B2858F-856F-4618-90DF-B42349E0A0FF}\InprocServer32]
@="C:\\OTSProjects\\PythonForExcel\\pfeControlShell\\Debug\\pfeControlShell.dll"
"ThreadingModel"="Both"
[HKEY_CLASSES_ROOT\CLSID\{40B2858F-856F-4618-90DF-B42349E0A0FF}\ProgID]
@="pfeControlShell.CoControlShell.1"
[HKEY_CLASSES_ROOT\CLSID\{40B2858F-856F-4618-90DF-B42349E0A0FF}\TypeLib]
@="{681382E5-EDDD-4509-AEBC-BDACE9F39E82}"
[HKEY_CLASSES_ROOT\AppID\{40B2858F-856F-4618-90DF-B42349E0A0FF}]
@="pfeControlShell.CoControlShell"
"DllSurrogate"=""
[HKEY_CLASSES_ROOT\TypeLib\{681382E5-EDDD-4509-AEBC-BDACE9F39E82}]
@="Python for Excel Control Shell Type Library"
[HKEY_CLASSES_ROOT\TypeLib\{681382E5-EDDD-4509-AEBC-BDACE9F39E82}\1.0]
[HKEY_CLASSES_ROOT\TypeLib\{681382E5-EDDD-4509-AEBC-BDACE9F39E82}\1.0\0]
[HKEY_CLASSES_ROOT\TypeLib\{681382E5-EDDD-4509-AEBC-BDACE9F39E82}\1.0\0\Win32]
@="C:\\OTSProjects\\PythonForExcel\\pfeControlShell\\Debug\\pfeControlShell.tlb"
[HKEY_CLASSES_ROOT\TypeLib\{681382E5-EDDD-4509-AEBC-BDACE9F39E82}\1.0\FLAGS]
@="0"
[HKEY_CLASSES_ROOT\TypeLib\{681382E5-EDDD-4509-AEBC-BDACE9F39E82}\1.0\HELPDIR]
@=""
The below is my registration file.
Windows Registry Editor Version 5.00
[HKEY_CLASSES_ROOT\pfeControlShell.CoControlShell]
[HKEY_CLASSES_ROOT\pfeControlShell.CoControlShell\CLSID]
@="{40B2858F-856F-4618-90DF-B42349E0A0FF}"
[HKEY_CLASSES_ROOT\CLSID\{40B2858F-856F-4618-90DF-B42349E0A0FF}]
@="pfeControlShell.CoControlShell"
"AppID"="{40B2858F-856F-4618-90DF-B42349E0A0FF}"
[HKEY_CLASSES_ROOT\CLSID\{40B2858F-856F-4618-90DF-B42349E0A0FF}\AppID]
@="{40B2858F-856F-4618-90DF-B42349E0A0FF}"
[HKEY_CLASSES_ROOT\CLSID\{40B2858F-856F-4618-90DF-B42349E0A0FF}\InprocServer32]
@="C:\\OTSProjects\\PythonForExcel\\pfeControlShell\\Debug\\pfeControlShell.dll"
"ThreadingModel"="Both"
[HKEY_CLASSES_ROOT\CLSID\{40B2858F-856F-4618-90DF-B42349E0A0FF}\ProgID]
@="pfeControlShell.CoControlShell.1"
[HKEY_CLASSES_ROOT\CLSID\{40B2858F-856F-4618-90DF-B42349E0A0FF}\TypeLib]
@="{681382E5-EDDD-4509-AEBC-BDACE9F39E82}"
[HKEY_CLASSES_ROOT\AppID\{40B2858F-856F-4618-90DF-B42349E0A0FF}]
@="pfeControlShell.CoControlShell"
"DllSurrogate"=""
[HKEY_CLASSES_ROOT\TypeLib\{681382E5-EDDD-4509-AEBC-BDACE9F39E82}]
@="Python for Excel Control Shell Type Library"
[HKEY_CLASSES_ROOT\TypeLib\{681382E5-EDDD-4509-AEBC-BDACE9F39E82}\1.0]
[HKEY_CLASSES_ROOT\TypeLib\{681382E5-EDDD-4509-AEBC-BDACE9F39E82}\1.0\0]
[HKEY_CLASSES_ROOT\TypeLib\{681382E5-EDDD-4509-AEBC-BDACE9F39E82}\1.0\0\Win32]
@="C:\\OTSProjects\\PythonForExcel\\pfeControlShell\\Debug\\pfeControlShell.tlb"
[HKEY_CLASSES_ROOT\TypeLib\{681382E5-EDDD-4509-AEBC-BDACE9F39E82}\1.0\FLAGS]
@="0"
[HKEY_CLASSES_ROOT\TypeLib\{681382E5-EDDD-4509-AEBC-BDACE9F39E82}\1.0\HELPDIR]
@=""