Vault database restoration/restoration Problems

When the system crashes or the vault library is migrated from one computer to another, the problem may be solved by restoring or restoring the original vault database, I thought it would work normally. Which of the following errors will be reported:
"Vault failed to establish a connection to the database ".

Here is a solution for me:
1. unmount the vault from the control panel.Be sure to select "retain" when asking if you want to retain the original database"
2. then reinstall the vault.Note: select "yes" when asking if you want to use the existing database ".
3. After installation, you can use the user and password in the original vault database to log on to and use the vault.
If you have any questions about the vault, visit http://support.sourcegear.com/to find the answer,
This is an English website. You must understand English.