It is difficult to delete old public folder from EMC. How to do it, use the ADSIEDIT to clear the old ones.
Right click on the folder you want to delete from CN=Exchange Administrative Group, CN=Databases, and click delete. The go to Active directory Sites and Services and initiate the replication across the domain.
Go to EMC and refresh.
Thats it.
Exchange Pre-Deployment Analyzer..Click here
The ExPDA tool performs a scan of your existing Exchange and Active Directory environments and produces a report that lists all items that require attention prior to deployment.
Exchange Server Profile Analyzer..Click here
The EPA tool performs a scan of either a single database or the entire organization to create an aggregated report of mailbox statistical information.
Log Parser…Click here
Log Parser, a powerful tool for querying text-based log files such as those that are generated by IIS and Message Tracking on Exchange servers
Exchange Server Remote Connectivity Analyzer..Click here
This tool will help you analyze whether the configuration has been done properly.
Performance Monitor..Click here or click here
The built-in Performance Monitor tool for Windows lets you collect performance data for every element of the Exchange servers and use it for capacity planning of the new Exchange 2010 servers.
Mailbox Server Requirements Calculator…Click here
The most complicated server role in an Exchange Server 2010 environment to calculate the sizing for is the Mailbox Server role, particularly when it comes to storage.
Please find on my blog, one page dedicated to this task…you can see it on my blog top page… or click here
TO 
MIGRATION…Started on June 8, 2010 ….Today 20th of June..all the objects has been replicated to Exchange 2010..Now the decommissioning starts..Finish too
Error
Microsoft.Exchange.Management.Deployment.UpdateRmsSharedIdentity.Link()
This error occurs because the federated built-in e-mail account that links to the computer account no longer exists. Or, the federated built-in e-mail account in the Active Directory directory service is corrupted.
Resolution..go to Active Directory server
Useful link : http://support.microsoft.com/kb/978776
PREMNAIR'S Blog 