A perfect horror for the season

computer, erase holodeck history?

Found the changeling.

But then when they were trying to find Bartlett, they just waltz right in to his sexual fantasy. You'd figure they'd have a "your commanding officer is looking for you, knows you're in here, and this is the knocking, so save and exit the program and pull your pants up if you need to."

They did point out that they would be breaking rules/regulations by entering the holodeck while he was using it, but from what I remember of the episode, he was absent from work, and wasn't responding to intercom pings, so they went to see him personally.

They did need to use command codes to force entry, so it might not normally be possible for civilians.

Though with holodeck technology, it's a wonder they even bother exploring the universe. That might be the most unrealistic part of Star Trek.

The Federation values real things, and people would get bored of fakery after a point. It costs you the same to take a trip to Vulcan as it does to walk into your holodeck and simulate a Vulcan sunset.