I recently visited an “Outside School Hours Care” centre (ie a centre that looks after school kids, outside school hours… usually before school, or after school… it helps parents handle unusual work hours).

They have 2 networked computers, which were behaving strangely… after a few questions, I got some unusual answers:

• sometimes PC1 would be unable to get to the internet.
• sometimes PC2 would be unable to get to the internet.
• sometimes both PCs wouldn’t get to the internet.
• and other times, their admin software (while reading data from the other PC over the network), would give network errors.
• The schools (unfriendly) IT tech, said the ethernet port had failed, and installed a PCI ethernet card to get them going.

At first I though it might be a virus infection… but then I noticed they had a wireless modem router… When I ask about it, I’m told it was installed a few months ago (the previous modem had broken down)… but they didn’t know if the WiFi was active (they had no WiFi devices).

I’m then told their internet usage had skyrocketed over the last two months… and they have a caravan park next door… could that be the problem?

I think so.

The wireless was unsecured, so it wouldn’t have taken long for the word to spread amongst the caravan park…

I also mention that with the kind of file sharing they are using, they could find deleted files, corruption, etc.

It turns out they have had some unusual “missing documents” from the computers.

So I quickly enable WPA security, and do a spyware/virus scan.

The scan finds no infections. At least thats a relief.

With no more electronic “intruders” to worry about, everything seems to work smoothly. I even have some spare time to do some quick tuning and a defrag of the computers (with a big improvement in speed).