Hi,
It seems that there is no exclude setting in the default Managemnent Pack. You may need to make some change in Configuration.xml.
Please check if the following thread will help:
http://www.winserverkb.com/Uwe/Forum.aspx/mom/8184/Exchange-MP-Can-I-exclude-individual-stores-from-monitoring
For more information, please refer to:
http://technet.microsoft.com/en-us/library/dd351258.aspx
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