Insert Outlook Message into Excel cell
 

Just was asked this today so also posting here for reference.

Probably the simplest method is to open Outlook, Word and Excel all at
once and use Word as an itermediary.

Copy-paste or drag the message to Word from Outlook.

Now copy-paste or drag the message to Excel from Word.

Word works with Outlook and puts the message as a package
automatically in a document, Excel works with Word in copied objects.