Disable .msg file preview error pop-up

[katriik]

Hi,

I have a specific condition: I love using the Preview Pane.
Unfortunately, it is not compatible with Outlook 64 bits, and I'm not into installing the 32 bits version due to all the other benefits from the 64 bits Office version.

On File Explorer, whenever you click on a .msg file while the Preview Pane is open, the following error pops up:
“Either there is no default mail client or the current mail client..."

So I started a fight to disable this error message. I'm not attempting to fix the problem, just disable the error message.
After multiple attempts, I successfully found out that deleting the key with data value of "Microsoft Windows MAPI Preview Handler" in HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\PreviewHandlers simply disabled any email preview in the Preview Pane.
Yay - no more pop-up blocking my work.

However, in Everything, the pop-up still shows up whenever I select a .msg file.

Does anyone know which registry key handles that so I can disable it?

Thank you very much.

[void]

Everything attempts to load preview handlers from:

HKEY_CLASSES_ROOT\.ext\ShellEx\{8895b1c6-b41f-4c1c-a562-0d564250836f}
HKEY_CLASSES_ROOT\class\ShellEx\{8895b1c6-b41f-4c1c-a562-0d564250836f}
HKEY_CLASSES_ROOT\SystemFileAssociations\.ext\ShellEx\{8895b1c6-b41f-4c1c-a562-0d564250836f}

In this particular case it is the preview handler in
HKEY_CLASSES_ROOT\SystemFileAssociations\.msg\ShellEx\{8895b1c6-b41f-4c1c-a562-0d564250836f}

[katriik]

Thank you @void.

It worked perfectly.