First off, when you say it "doesn't accept a tape", do you mean it
spits out the tape when it is inserted ot does the unit not take the
tape at all?

If it takes it and spits it out: Do you have a timer recording set?
When you are setting the clock, it maybe activating any set programs.
If so, some VCRs require either a tape with the protection tab intact,
or no tape when it is turned off. I have a panasonic VCR that does the
exact same thing when the clock it is set. Just put a blank tape in to
fix it.

If it doesn't attempt to take any tape, it may have bad logic
circuitry. At worst, don't set the clock.