User errors: Lots of time the duplicate email occurs while manually copying and pasting meetings and appointments in the Outlook Calendar.Synchronization issues: Due to sync problems we have also observed duplicated contacts and messages.

Anti-virus issues: Sometimes even your anti-virus software may also create duplicate e-mails.

Rules not configured correctly: At times it is also found that the rules and guidelines not configured properly set, this results in multiple instances of the same messages.

Incorrect account setup: In numerous cases, the problem arises due to incorrect email account setting and this results in multiple instances of each incoming email, contacts and calendar entries.

In order to remove duplicate emails in outlook pst file, you have to check many things which cause Outlook items to duplicate, but the most common reasons are discussed below:

Reasons for duplicate emails appearing in Outlook Software Guide to Remove Outlook Duplicacy.Manual method Remove Duplicate PST files.Techniques to Remove Duplicate Emails in Outlook.Reasons for duplicate emails appearing in Outlook.

Delete duplicates in outlook folder