Mac OS X 10.6.1 Mail is showing duplicated incoming messages

[LoganM]

I am facing some issues with my Mac OS X 10.6.1. I most often find my incoming email messages to be duplicated. I am using Microsoft Exchange account and it is having the same time/date as my system. Can you help me how to solve this matter?

[deveritt]

It is because of <com.Apple.Mail.plist> file. You can find this file by going to Home folder, Library, Preferences Not PreferencePanes. Once you got this file, move this file onto your Desktop. Now launch your Mail Program and this time you should see everything as normal. If it is true then delete that file from your Desktop but if it isn't then reposition this file in its original position.

[LoganM]

Thank you and this fix worked for me too. But I would like to know why and how it occurred? I don't want to get that problem once again. Why does mail gets duplicated? What steps should I implement to prevent it? Does that happen because I opened 2 mail on different windows?

[Trio]

Even I am having similar problems and I tried removing the plist file but it didn't worked. In fact because of this I lost all of my emails. I have saved my emails once and so I was able to recover it. Is there any download for this application which is supposed to remove duplicate messages in Apple Mail?

[johnson22]

Which email client are you using instead of this? Why don't you use Gmail or some other webmail to host your emails? And Trio, I think you have missed some of the points that have been said so far. It will help you.