Restored security file is either damaged or is not from a backup for this company
Sage 50 is rejecting the security portion of your restore because it does not match the company or is corrupt.
You restored a backup, and Sage 50 refused the piece of it that holds users, roles, and permissions. The message reads:
The restored security file is either damaged or is not from a backup for this company.
In plain terms, Sage 50 keeps security settings in a separate component of the backup. During a restore it checks that this component belongs to the same company file being restored. The check failed, so the restore stopped. Usually this is a mismatch, not damage: the security data came from a different company, a different backup, or a copy operation that broke the pairing.
Why the pairing check exists
Security settings are tied to the specific company file they were created in. Sage 50 will not attach one company’s user list and permissions to another company’s data, because that could grant or deny the wrong people access. When the check fails, the software cannot tell a corrupted file from a swapped one, so it stops either way.
Check that the backup and the company file match
The most common cause is restoring a backup against the wrong company, or restoring a backup that was copied incompletely. Confirm the backup set is complete and was made from the company you are restoring into. If more than one backup exists, try the most recent one taken from that same company. If the restore then succeeds, the earlier set was simply mismatched or incomplete.
Restore to a fresh location
A leftover security component from a previous restore can collide with the new one. Restore into a new, empty folder rather than over an existing company, and let Sage 50 create everything from scratch. This rules out half-written files from an earlier attempt.
Copy the backup again
If the backup traveled over a network, a USB drive, or a cloud folder, it may have arrived truncated. Copy the backup set again and compare it against the original. A backup that fails to copy cleanly will fail to restore cleanly.
When the security component really is damaged
If every backup of the company fails the same way, the security data itself is likely corrupt. Sage 50 has no user-facing repair for that component. Our engineers can evaluate the backup and, in most cases, recover the company data and rebuild the security settings so users and permissions work again. Whether a full recovery is possible depends on the file, so we assess it before quoting anything.
A useful next step
Stop trying further restores; each attempt against a damaged set adds confusion without adding information. Gather every backup you have of the company, note which one produced this message, and send them for a free evaluation of your Sage 50 backup. We will tell you what is recoverable and what a repair would involve before you commit to anything.