To fix a SQL Server backup compression error, start by verifying that your SQL Server edition supports backup compression, as some editions like Express do not. Ensure there is enough disk space for the compressed backup file. Check for database corruption by running DBCC CHECKDB on the database; repair issues if necessary. Update SQL Server to the latest service pack or cumulative update, as compression bugs may be fixed in newer versions. If the error persists, try disabling compression temporarily using WITH NO_COMPRESSION in your BACKUP DATABASE command to confirm the issue is compression-related. For severely corrupted databases or persistent errors, professional tools Aryson SQL Database Recovery Software can repair MDF/NDF files, recover database objects, and allow backups without data loss, ensuring your SQL Server environment remains stable.