When upgrading Symantec Endpoint Protection Manager (SEPM) from version 14 RTM (v.14.0.1904.0000) , version 14 MP1 (v.14.0.2332.0100) or version 14 MP1 refresh (v.14.0.2349.0100) to newer you are prompted for SQL SA credentials.
This issue is resolved in Symantec Endpoint Protection (SEP) 14 MP2. For more information on upgrading, please see Upgrade or migrate to Endpoint Protection 14.
Workaround is to provide SA credentials.