You are trying to install or upgrade a Symantec Endpoint Protection Manager (SEPM) but the configuration wizard continues to return to database authorization dialog; it appears to be failing but there is no visible error message explaining why. The account username for SQL authentication may contain a special character, e.g. a hyphen or period.

Error found in SEPM install.log

2017-11-17 16:51:29.352 THREAD 36 INFO: Begin NT impersonation for user: xx/x.xxxxxx
2017-11-17 16:51:29.464 THREAD 36 INFO: End NT impersonation 
2017-11-17 16:51:29.581 THREAD 36 WARNING: DbUtil> addReporterUser>> Add report login!
2017-11-17 16:51:30.089 THREAD 36 WARNING: Upgrade> updateTransactionLogFileSize>> Original log size is 2097152
2017-11-17 16:51:30.091 THREAD 36 SEVERE: com.microsoft.sqlserver.jdbc.SQLServerException: Incorrect syntax near '.'.
2017-11-17 16:51:30.091 THREAD 36 SEVERE:     at com.microsoft.sqlserver.jdbc.SQLServerException.makeFromDatabaseError(SQLServerException.java:217)
2017-11-17 16:51:30.091 THREAD 36 SEVERE:     at com.microsoft.sqlserver.jdbc.SQLServerStatement.getNextResult(SQLServerStatement.java:1635)
2017-11-17 16:51:30.091 THREAD 36 SEVERE:     at com.microsoft.sqlserver.jdbc.SQLServerPreparedStatement.doExecutePreparedStatement(SQLServerPreparedStatement.java:426)
2017-11-17 16:51:30.091 THREAD 36 SEVERE:     at com.microsoft.sqlserver.jdbc.SQ

There is limited special character support for usernames used to authenticate SEPM with SQL, but these requirements are not consistently enforced or documented.

Workaround is to change the account used for SQL authentication with an account which username does not contain any special characters.

Improvements made in SEP 14.2 for more consistent enforcement of username requirements. See Account name and password requirements for Endpoint Protection.