Error The Exchange certificate operation has failed with an exception on server . The error message is Access denied.

I am getting this error message when I am trying to open the certificate details from the Exchange 2013 ECP.
"Error The Exchange certificate operation has failed with an exception on server . The error message is Access denied. "
I am able to see the certificate details from the Power Shell.

How to fix the issue? 
After adding the Exchange Trusted subsystems as a local administrator on the server fixed the issue. 

Find out how many users are using Pop3 or IMAP in exchange Server (using log parser studio)

To Know the number of users connecting to exchange server for pop3 or IMAP , you have to enable protocol logging.

How to enable Protocol Logging?

Set-ImapSettings -Server "CAS01" -ProtocolLogEnabled $true
Set-PopSettings -Server "CAS01" -ProtocolLogEnabled $true

Restart the Pop3, Pop3 Back end, IMAP and IMAP Back end service.

Unless you change the path, you will find the logs in default path 

C:\Program Files\Microsoft\Exchange Server\V15\Logging\POP3

C:\Program Files\Microsoft\Exchange Server\V15\Logging\IMAP 

You can follow this document for enabling and limiting the log size.

Wait for some time, so the protocol log will be able to capture the logs. 

You can use log parser studio to analyze the logs. 

This small query can help you to find out how many users are connecting and accessing which mailbox. 

/*  New Query  */

select 
 user as Username,
 parameters AS Mailbox, 
 Count(*)
 FROM '[LOGFILEPATH]'
 WHERE Username NOT LIKE '%Health%' AND Username IS NOT NULL AND Mailbox NOT LIKE '%Health%' AND Mailbox IS NOT NULL
 Group BY Username, Mailbox
 Order BY Username

Rename the Default Mailbox database created during the exchange server 2013 installation.

Rename the Default Mailbox database created during the exchange server 2013 installation. 

Exchange server creates a mailbox database like "Mailbox Database XXXXXXXXXX, if you have used graphical mode or did not specify the database name in power-shell during exchange 2013 installation.  (In this installation Exchange created  "Mailbox Database 2040311832")

The mailbox database is located in the default path “C:\Program Files\Microsoft\Exchange Server\V15\Mailbox” 

Follow the below steps to rename and move the database to another path.

Get-Mailboxdatabase  "Mailbox Database 2040311832"  | Dismount-Database

It will prompt you to confirm. Click Yes to dismount the database. 

 

Use the below command to move the database to another path. I am moving the mailbox database to path "C:\MailboxDBs\MDB01.DB” and renaming the EDB to MDB01.edb. Also moving the Logs to folder  “C:\MailboxDBs\MDB01.LOG”

Move-DatabasePath "Mailbox Database 2040311832" -EdbFilePath "C:\MailboxDBs\MDB01.DB\MDB01.edb" -LogFolderPath "C:\MailboxDBs\MDB01.LOG"

Click on yes, when it asks for confirmation. 

Mount the database

Get-Mailboxdatabase  "Mailbox Database 2040311832"  | Mount-Database

Now the database is moved to the new path but the mailbox database display name is still showing the old name. You can use the below command to rename it

Get-Mailboxdatabase "Mailbox Database 2040311832" | Set-MailboxDatabase -Name "MDB01"

Or you can use graphical mode to rename it. 

Click on save to change the DB name.