Falls Du von Hand nicht weiterkommst: NirSoft Mail PassView v1.86

https://www.nirsoft.net/utils/mailpv.html



Mail PassView is a small password-recovery tool that reveals the passwords and other account details for the following email clients:

Outlook Express
Microsoft Outlook 2000 (POP3 and SMTP Accounts only)
Microsoft Outlook 2002/2003/2007/2010/2013/2016 (POP3, IMAP, HTTP and SMTP Accounts)
Windows Mail
Windows Live Mail
IncrediMail
Eudora
Netscape 6.x/7.x (If the password is not encrypted with master password)
Mozilla Thunderbird (If the password is not encrypted with master password)
Group Mail Free
Yahoo! Mail - If the password is saved in Yahoo! Messenger application.
Hotmail/MSN mail - If the password is saved in MSN/Windows/Live Messenger application.
Gmail - If the password is saved by Gmail Notifier application, Google Desktop, or by Google Talk.