No, you do not need Microsoft Outlook installed to remove duplicate items from MSG files if you use a best tool like TrustVare MSG Duplicate Remover. This software works independently of Outlook and scans MSG files like emails, attachments, etc, to find duplicate items and removes them wihtout harming original data. It identifies duplicate emails using multiple parameters such as subject, sender, date, body, and attachments. The tool removes duplicates without downloading any software on the PC. It will support all Windows OS versions like 11, 10, 8.1, 8, and 7. You can try the free demo version and see their removal process.

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