Skating problem

[Jeremy]

I've been borrowing a cheap Pioneer turntable that's several years old in order
to convert some records to CD's. After not using it for 3 or 4 months I put a
record on it this evening and immediately had a severe skating problem. One
time it even skated from the first track all the way to the paper center. Now,
I have kept this unit in a somewhat remote area of the house and to my knowledge
nobody has messed with it. What could have caused this problem? Is the stylus
damaged and do I need to replace the cartridge? I tried adjusting both the
anti-skate settings and counterbalance both ways but it seems to make no
difference whatsoever. I'm a newbie when it comes to turntables so keep that in
mind.

Thanks in advance,
JC