Do the following steps in order.

1. Move the SAI and SAJ to a new folder on the C:\\ drive.
2. Open the sample company.
3. If the sample company doesn't get the same error, restore a backup made before receiving the error.
4. Continue to the next steps, if you receive the same error in the sample company.
5. Ensure you’re using the latest version of Sage 50.
6. Complete all Windows updates by going to Windows Start, Control Panel, Windows Updates, Check for Updates.
7. Check which firewall you're using and that it's configured correctly to work with Sage 50.
8. Complete an advanced reinstall of Sage 50.
9. Restart the computer.

Error: "Database engine timed out" when opening a company file over the network