ACS print sessions credentials prompt

I am having problems with preventing being prompted for credentials when starting an ACS print session.

When I start a print session and answer the credentials prompt and then close the print session and restart it I don't get prompted for credentials, they are cached.

I have tried to cache the credentials like this :
acslaunch_win-64.exe /PLUGIN=logon /SYSTEM=(system) /USERID=(userid) /PASSWORD=(password) /AUTH to cache the credentials before starting the print session.
Followed by starting the print service.

I still get prompted for credentials for the print session.
What am I doing wrong?

Thanks,
Monty

________________________________

This email message, including any attachment(s) is for the sole use of the intended recipient(s) and may contain confidential information. Any unauthorized review, use, disclosure or distribution is strictly prohibited. If you are not the intended recipient, please immediately contact the sender by email.