I am using Exchange 2010 with SP1 and I am unable to access one mailbox servers. But, I can access other two mail servers without any problem. I think Exchange Search Indexer service keeps stopping. I have tried to disable it, but, that didn’t work. Please, help you with this.
Unable to access one of the three mailbox server
Hi Imelda_Granger,
   If you're using Exchange 2010 with SP1 and you're unable to access one mailbox server is because all account should be granted permission to be able to access mailbox server.  Might probably your 2 mail servers has permissions and the third has'nt.
   You have to go to Exchange Management Shell and run the command to grant you another permission to access your mail server. You have to type the command below:
New-RoleAssignmentManagement -Role "Mailbox Export Import"- User Administrator
  Then, if you're already logged with that user  and to be able to have fully access , you have to restart your Exchange Management Shell application.
Hope this might help you.
Thanks.
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