I have tried to do all the things above but I am still having troubbles, the error message that I am receiving is : Unistall cannot continue Summary: 2 item(s). 1 succeeded, 1 failed. Elapsed time: 00:00:17 Mailbox Role PrerequisitesFailed Error:Uninstall cannot continue. Database 'Public Folder Database': Exchange is unable to check for public folder replicas for the public folder database that you specified. Verify the Microsoft Information Store service is running, and that the database is properly mounted. Specified public folder database: "SERVER\Second Storage Group\Public Folder Database".Recommended Action: http://go.microsoft.com/fwlink/?linkid=30939&l=en&v=ExBPA.3&id=b6e3b32a-8848-46cb-9567-72288ac15f60 Elapsed Time: 00:00:14 Organization PrerequisitesCompleted Elapsed Time: 00:00:03 i I hope someone could help me.