I ran into an interesting case the other day with a client, so thought I would share it with the community.
Software: Presentation Server 4.5 (Roll up 5), Server 2003
Problem: Client complained of issue with installing roll-up pack 7 for presentation server. He was upgrading from the roll-up 5 level. After the install was completed for roll-up 7, his Citrix SMA service failed to start. He got 2 different errors, one said to check the permissions on the account. The other error said that the service started, but immediately stopped — possibly because it had nothing to do.