{"id":49344,"date":"2020-01-27T15:14:33","date_gmt":"2020-01-27T15:14:33","guid":{"rendered":"https:\/\/www.stellarinfo.com\/blog\/?p=49344"},"modified":"2024-11-05T07:02:07","modified_gmt":"2024-11-05T07:02:07","slug":"error-solved-the-copy-of-database-on-this-server-was-unexpectedly-dismounted","status":"publish","type":"post","link":"https:\/\/www.stellarinfo.com\/blog\/error-solved-the-copy-of-database-on-this-server-was-unexpectedly-dismounted\/","title":{"rendered":"[Solved]: The Database on this Server was Unexpectedly Dismounted"},"content":{"rendered":"

Exchange and IT admins often encounter various issues and errors when working with the Exchange Server. One common error is:<\/p>

Source: ExchangeStoreDBEvent ID: 225<\/em><\/p>

Task Category: General<\/em><\/p>

Level: Error<\/em><\/p>

The copy of database ‘MDB-PDJ-EXC-2’ on this server was unexpectedly dismounted. The error returned by failover was “There is only one copy of this mailbox database (MDB-PDJ-EXC-2). Automatic recovery is not available.” For more specific information about the failures, consult the event log on the server for other “ExchangeStoreDb” events.<\/em><\/strong><\/p>

If the database is dismounted from Exchange Server, then it prevents the users from accessing their mailboxes or sending and receiving emails, leading to downtime. When you try to mount the database again, it fails to mount. This might happen due to some underlying issues with the Exchange Server or any other reason. Below, we will look into the reasons behind the ‘Database on this server was unexpectedly dismounted’<\/em><\/strong> error and see how to resolve it.<\/p>

Understanding the Issues behind the Database Dismounted Unexpectedly Error<\/strong><\/h2>

As indicated from the above error message, you can check the Event Log to get more information and find out the underlying cause. For this, navigate to the Event<\/strong> Viewer<\/strong> and select the Application<\/strong> log. Filter the events by setting the source to MSExchangeIS<\/strong> (Microsoft Exchange Information Store). This will narrow down the events relevant to the Exchange Information Store. You may find the following events:<\/p>

1. Event ID: 1001<\/strong><\/p>

Log Name: Application<\/em><\/p>

Source: MSExchangeIS<\/em><\/p>

Event ID: 1001<\/em><\/p>

Task Category: General<\/em><\/p>

Level: Error<\/em><\/p>

Microsoft Exchange Server Information Store has encountered an internal logic error. Internal error text is (Unable to apply maintenance insert, index corruption?<\/em><\/p>

2. Event ID: 1002<\/strong><\/p>

Log Name: Application<\/em><\/p>

Source: MSExchangeIS<\/em><\/p>

Event ID: 1002<\/em><\/p>

Task Category: General<\/em><\/p>

Level: Error<\/em><\/p>

Unhandled exception (Microsoft.Exchange.Diagnostics.ExAssertException: ASSERT: Unable to apply maintenance insert, index corruption?<\/em><\/p>

3. Event ID: 4999<\/strong><\/p>

Log Name: Application<\/em><\/p>

Source: MSExchange Common<\/em><\/p>

Event ID: 4999<\/em><\/p>

Task Category: General<\/em><\/p>

Level: Error<\/em><\/p>

Watson report about to be sent for process id: 11204, with parameters: E12, c-RTL-AMD64, 15.00.0712.024, M.E.Store.Worker, M.E.S.Storage.LazyIndexing,<\/em><\/p>

M.E.S.S.L.LogicalIndex.HandleIndexCorruptionInternal, M.E.Diagnostics.ExAssertException, 213a, 15.00.0712.000. ErrorReportingEnabled: True<\/em><\/p>

As you can see, the event IDs 1001 and 1002 indicate index corruption, and the event ID 4999<\/a> indicates a failed or unexpectedly terminated process. Now, let’s see how to resolve these issues and mount the database back on the server.<\/p>

Methods to Resolve the Database on this Server was Unexpectedly Dismounted Error<\/h2>

Here are some methods you can try to fix the Database on this server was unexpectedly dismounted error and mount the database again.<\/p>

Method 1: Disable the Indexing<\/strong><\/p>

If the search index gets corrupted, it can cause the database to dismount from the server. To see if the search index is causing the issue, you can disable the index for the specific database or the entire server.<\/p>

Note:<\/strong> Disabling the index will affect the database performance and slow search results.<\/p>

To disable search index for a single database, you can use the Set-MailboxDatabase<\/strong> PowerShell<\/strong> cmdlet in EMS<\/strong> (see the below example).<\/p>

Set-MailboxDatabase <database name> –IndexEnabled $False<\/strong><\/code><\/pre>
\"To<\/figure>
To disable Exchange search service for the entire server, you need to stop the Microsoft Exchange Search<\/strong> service. To do so, use the following command in the PowerShell:<\/p>
Stop-Service MSExchangeFastSearch \n\nSet-Service MSExchangeFastSearch –StartupType Disabled<\/code><\/pre>
\"Set<\/figure>
If the error is resolved after disabling the search index, this is an indication that there are issues with the Exchange Search index. In such a case, you can diagnose Exchange Search issues<\/a>.<\/p>
Method 2: Restart Microsoft Exchange Information Store Service<\/strong><\/p>
It might happened that the Microsoft Exchange Information Store Service is stopped or crashed, leading to the database dismount issue. You can check and start the service to resolve the issue. Follow the steps mentioned below:<\/p>
    \n
  1. Press Windows + R<\/strong> to open the Run dialog box.<\/li>\n\n\n\n
  2. Type services.msc<\/em> and press Enter<\/strong>.<\/li>\n\n\n\n
  3. In the list of services, locate Microsoft Exchange Information Store<\/strong>.<\/li>\n\n\n\n
  4. Right-click on the service and select Start<\/strong> or Restart<\/strong>, depending on its current state.<\/li>\n<\/ol>
    \"Right<\/figure>
    After restarting the services, try to mount the database<\/a> on the server. If the issue persists, follow the next method.<\/p>
    Method 3: Repair the Exchange Database<\/strong><\/p>
    If the above mentioned methods fail to resolve the error, then this means that the database is corrupted or inconsistent. In such a case, you can try to repair the database using the EseUtil commands. Here’s how:<\/p>