SharePoint Config database logs are one thing to keep an eye on since they do have a tendency to grow. If you don’t perform a full farm backup usually the log doesn’t get emptied and it just keeps bloating.
If you’re running SQL Server Express with default installation, you can find the files in C:Program Files\Microsoft SQL Server\MSSQL.1MSSQLData
As we see in the example above, even though the database is only 9 gig, the log file grew to 34 gigs. Let’s reduce that:
1. If you don’t have it yet, download and install SQL Server Management Studio express from here.
2. Run the Management Studio and connect to your SQL Server.
3. Expand “Databases” and select your config database “SharePoint_Config”.
4. Right Click it, select Tasks –> Shrink –> Files
5. In the new window select Release unused space and click OK.