KB4486940 - FIX: Assertion failure occurs when you try to back up database in limited disk space in SQL Server 2016 and 2017

Applies to: SQL Server 2016 DeveloperSQL Server 2016 EnterpriseSQL Server 2016 Enterprise Core


Assume that you have Microsoft SQL Server 2016 or 2017 installed. If you try to back up the database in limited disk space, then the backup operation may fail. In addition, when you try to cancel the backup operation, an assertion failure error that resembles the following may occur:

DateTime spid#      SQL Server Assertion: File: <FileName>, line=LineNumber Failed Assertion = '0'. This error may be timing-related. If the error persists after rerunning the statement, use DBCC CHECKDB to check the database for structural integrity, or restart the server to ensure in-memory data structures are not corrupted.


Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section. 


This issue is fixed in the following cumulative updates for SQL Server:

About cumulative updates for SQL Server:

Each new cumulative update for SQL Server contains all the hotfixes and all the security fixes that were included with the previous cumulative update. Check out the latest cumulative updates for SQL Server:


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