As a SQL Server user, you may have encountered various errors while working with the database. In this blog post, we will discuss one such error and its solution.

Recently, while running a backup command, I encountered an error related to the BackupDirectory Registry Key. The command I used to run was:

BACKUP DATABASE [SQLAuthority] TO DISK = N'SQLAuthority.bak'

However, when I ran the command, I received the following error:

Msg 3047, Level 16, State 1, Line 1
The BackupDirectory registry key is not configured correctly. This key should specify the root path where disk backup files are stored when full path names are not provided. This path is also used to locate restart checkpoint files for RESTORE.
Msg 3038, Level 16, State 1, Line 1
The file name “SQLAuthority.bak” is invalid as a backup device name. Reissue the BACKUP statement with a valid file name.
Msg 3013, Level 16, State 1, Line 1
BACKUP DATABASE is terminating abnormally.

This error occurs when the BackupDirectory registry key is not configured correctly. The key should specify the root path where disk backup files are stored when full path names are not provided. In my case, I had mistakenly messed up this setting.

To resolve this issue, follow these steps:

1. Open SQL Server Management Studio.
2. Connect to the SQL Server instance where the error occurred.
3. Right-click on the instance and select “Properties”.
4. In the “Properties” window, navigate to the “Database Settings” tab.
5. Under the “Backup” section, enter the correct path in the “Backup” textbox.
6. Click “OK” to save the changes.

Once you have entered the correct path in the “Backup” textbox, the backup command should work as expected.

It’s important to note that this error can be easily avoided by providing the complete path of the backup file in the backup command. However, if you prefer to use the default backup directory, make sure the BackupDirectory registry key is configured correctly.

So, next time you encounter the BackupDirectory registry key error, remember to check the settings and make the necessary corrections. Happy SQL Server troubleshooting!