cannot import or edit certificate in Exchange 2010 - access is denied

Issue:
When you try to edit or import or modify certificate using powershell of EMC you might get the error:
(PID 980, Thread 10) Task Get-ExchangeCertificate writing error when processing record of index 0. Error: Microsoft.Exchange.Data.Common.LocalizedException: The Exchange Certificate operation has failed with an exception. The error message is: Access is denied ---> System.ComponentModel.Win32Exception: Access is denied
--- End of inner exception stack trace ---
Solution:
to Fix this issue make sure that the Exchange server is member of the following:
- Exchange Trusted Subsystem group nested in the local admins group on all your CAS/HT boxes.
- Exhachnge servrs are members of this group.
then Restart the servers after any modifications to group membership.