It seems the backup file has been corrupted and cannot restore, Just to make sure your SQL Database is healthy and clean… please execute DBCC CHECKDB on that database. After the successful completion dbcc checks, Initiate one more backup with the current database and verify that backup file before restoring.
when you completed your SQL Backup it is recommended to verify that backup file immediately.
If you are able to success to execute the below command against the master DB, then only you are able to restore.
RESTORE verifyonly FROM DISK=’D:\DB.bak’;
(D:\DBb.bak is the backup file location)
Above query must give you, “The backup set on file 1 is valid.”
RESTORE VERIFYONLY command verifies the backup but does not restore it, and checks to see that the backup set is complete and the entire backup is readable. However, RESTORE VERIFYONLY does not attempt to verify the structure of the data contained in the backup volumes
Checks performed by RESTORE VERIFYONLY include:
- That the backup set is complete and all volumes are readable.
- Some header fields of database pages, such as the page ID (as if it were about to write the data).
- Checksum (if present on the media).
- Checking for sufficient space on destination devices.