Hi, s-l. LTNS as they say these days.

My ancient Dells used to complain about intrusion whenever I'd opened them up for anything - since they then went on and worked fine, I didn't trouble to figure out how the intrusion detection system worked. Probably all changed by now!

It might be worth checking to see that the computer case - I assume it's a tower of some sort - is properly closed up. If there's a gap in its panels, that might be triggering an intrusion alert.

If it's not that simple (I honestly doubt whether it is), then it might be worth opening it up and physically checking the security of the cable it's complaining about. Try to find a maintenance manual online, perhaps, or simply check for any loose cable that looks as if it should be connected to something that looks like a microswitch/proximity switch or whatever that would be opened if the casing is opened.

I suppose you need to be a little wary about giving the seller an excuse to duck a refund on the grounds that you've done something to the machine - your call!

No idea about the freezing problem. It MIGHT be related to a hardware fault which also causes the intrusion warning, or it might be a purely software-related matter. Have you done an internet search with the details of the error message? There might be something out there.

You might also consider looking for a Dell user forum, if there is such a thing, and see whether anyone has experienced the same thing.

I tried to post earlier, but the site ate my posting. Having had the usual nonsense with having to slog through reCaptcha (sp?) rubbish, I was Jolly Cross and stomped off in a huff. At least the reCaptcha stuff has saved me some money. I just couldn't be bothered trying to log into my buying account, either!

(I've done this in a text editor - on past performance, the site will helpfully remove any trace of paragraphing... if it doesn't simply wipe the whole thing. Disillusioned? Moi?)