I remember the first time an employer realized that I had access to everything . She froze for a few seconds while she processed the idea, shrugged, and went on with her request.
You're going to learn things you don't want to know and see things people don't expect you to see. My least favorite experience was someone who had an email stuck in their outbox. "Subject Re: Re: Re: Re: Re: My widdle wuvvy bear From: Not His Wife" And thank you so much, preview line, for confirming the content. So, with a straight face and chipper tone, "Next time a message gets stuck, you can just select it and hit delete." I didn't add, "And you, of all people, should know better than to use company email to conduct that sort of activity because we archive everything. I just did an archive search for you last month."
My most favorite was when I was helping someone with some simple thing and minimized her browser to discover that her desktop wallpaper was a picture of her frolicking in a bikini. Again, just go on like it's nothing out of the ordinary. Heck, if I looked like that, I'd want to look at me all day, too. Oh, and there was an intern who, when she finished her assignment, cleared everything off her desktop except a topless pic of herself.
If I'd seen evidence of blatant criminal activity or harassment, I would have reported it to the person's manager and my boss and let them deal with it. But politics and gossip and salaciousness were ignored. I was employed to keep the equipment running, not be the morality police.