Cannot perform a differential backup for database, because a current database backup does not exist

Before to solve the following issue: "Cannot perform a differential backup for database, because a current database backup does not exist" let's find out why this error message appears?

First of all, it is necessary to know that a differential backup contains all changes that have been made since the last full database backup. It means that during the restore process you need to restore your last full database backup and only then restore last differential database backup, but not the other way.

Cannot perform a differential backup for database, because a current database backup does not exist

The very first thing which it is necessary to check is if there is another backups software like Bacula, NTBackup, BE or etc., which takes a Volume Shadow Copies (VSS) or snapshots of your database. It can be a reason that the backup chain will be broken and a differential backup will be invalid. That's why when the next differential backup will be performed it will fail because of it can't find the previous full or differential backup. 

The Solution

First of all, you need to find out which software tool is creating snapshot backups of your database because there are several ways how you can solve this issue. Let's consider the most common case when snapshot backups are making with the help of NTBackup.

The Solution for NTBackup

Primarily, check SQL Server VSS Writer in the Service menu it has to have the following settings: Start Type: Manual and the service has to be stopped.

If SQL Server VSS Writer service is running and a snapshot is taken, the full recovery model will be blocked and the backup chain will be broken.

To change SQL Server VSS Writer settings go to the "Star Menu" and find "Services" in the opened window select "SQL Server VSS Writer".

Right-click the service and select "Properties", in the opened window set the "Startup Type" to "Manual", press "Stop" at the "Service status" section to make sure that service will not run automatically after you restart your computer and click "OK" to apply all changes.

Also, note, that you can face with this issue when you upgrade your SQL Server, for example, from SQL Server 2012 to SQL Server 2014 and during the installation all settings can be reset and SQL Server VSS Writer will be turned on again.