In This tweak %ACCOUNT% is the number corresponding to your IMAP account,  00000001, for example. You may need to search deeper in the keys to find it. 

Find out the name of your inbox, drafts and sent IMAP folders.

Key:HKEY_CURRENT_USER\Software\Microsoft\Internet Account Manager\Accounts\%ACCOUNT%

Data Value: 

"IMAP Root Folder" = inbox, 

"IMAP Drafts Folder" = drafts, 

"IMAP Sent Items Folder" = sent
Data Type: REG_SZ

 

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