During the troubleshooting of VMware Venter connection to SQL server error, VMware support changed SQL authentication mode from Windows/SQL mixed mode to Windows authentication, but SQL server won't allow us to change it back. See error message attached. I am not able to use sa account to login to SQL on local server anymore. After the VCenter to SQL connection issue was fixed, the Veritas backup job to SQL failed due to the domain admin account I am using on Backup server has insufficient permission (sysadmin) to take SQL snapshot. The backup job was running successful for months when both sa and the domain admin account are all good.
Need a SQL expert's help to let me know how I can switch back SQL authentication from Windows to Windows/SQL mixed mode so I can use sa to login.
Thank you in advance!