a play on words to mean looser, its looser and user combined, used by sysops.
I delete all of that lusers data from the network server, he should have backed it up.

<jargon, abuse> /loo'zr/ A user; especially one who is also a loser. (luser and loser are pronounced identically.) This word was coined around 1975 at MIT. Under ITS, when you first walked up to a terminal at MIT and typed Control-Z to get the computer's attention, it printed out some status information, including how many people were already using the computer; it might print "14 users", for example. Someone thought it would be a great joke to patch the system to print "14 losers" instead. There ensued a great controversy, as some of the users didn't particularly want to be called losers to their faces every time they used the computer. For a while several hackers struggled covertly, each changing the message behind the back of the others; any time you logged into the computer it was even money whether it would say "users" or "losers". Finally, someone tried the compromise "lusers", and it stuck. Later one of the ITS machines supported "luser" as a request-for-help command. ITS died the death in mid-1990, except as a museum piece; the usage lives on, however, and the term "luser" is often seen in program comments. See: also LART. Compare: tourist, weenie. [Jargon File] (1998-07-01)

<jargon> (LART) Something large, heavy and painful, used to respond appropriately to particularly annoying lusers. The alt.sysadmin.recovery FAQ recommends the following LARTs. A 2x4 works fine, but a real professional needs something a little more effective. Unfortunately, this is a very personal thing, and no consensus has yet been reached on the group. Everything from a simple, 7.65mm Walther (for the Bond fans only, it's not a very good gun) to a 155mm with depleted Uranium rounds has been suggested, some even going for exotic things like Thermite, nukes or flamethrowers. For further info, look at the rec.guns home page. {Luser Attitude Re-adjustment Toolingvar/asr/overview.html">alt.sysadmin.recovery FAQ (http://ctrl-c.liu.se/Luser Attitude Re-adjustment Toolingvar/asr/overview.html)}. (1998-12-09)