Word/Excel 201x preview pane errors

An oldie but a goodie. A user still running Office 2013 started receiving odd errors when trying to open both Word and Excel files. In each instance the error was completely different, but the issue/solution was the same. The problem only occurred when they were browsing for files via File Explorer, and the preview pane option was on.

Word pops up an error dialogue: Sorry, something went wrong and Word was unable to start. (24)
Excel simply throws an error dialogue with a red cross icon and no text.

Both applications still launch and run without a problem, and turning off the preview pane removes the issue. However, some users insist that they can’t work without the preview pane so a proper solution is required.

This all stems from some registry entries for the preview pane that are present but not populated (usually caused by the uninstallation of 64-bit Office, perhaps the preinstalled version that inevitably comes along with Win 1x being removed and replaced with a 32-bit install of an earlier version).

To resolve, fire up regedit and delete the following keys:

Microsoft Excel previewer:
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{00020827-0000-0000-C000-000000000046}
Microsoft PowerPoint previewer:
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{65235197-874B-4A07-BDC5-E65EA825B718}
Microsoft Word previewer:
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{84F66100-FF7C-4fb4-B0C0-02CD7FB668FE}
Microsoft Visio previewer:
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{21E17C2F-AD3A-4b89-841F-09CFE02D16B7}

Thanks to Cyann.net for the solution.