Hi,
You need to:
1. Ensure you have the correct DB Type selected under the Login options.
2. Verify that all connection information is correct (for example, the correct user name and password or the user has enough right to connect to the database server in case Windows Authentication is used).
3. Check whether the database is running properly, make sure that the COMMON and company databases are not suspended or stopped.
4. Ensure there is no DI API version mismatch.
Thanks & Regards,
Nagarajan