How does one copy cassette tapes to computer?

Rodman, thanks for the informative response.

What I was envisioning was the possibility that the mic input circuitry would be overloaded by a line-level signal before the signal information ever reached either the Windows software or the application software (Mixcraft in this case), unless the output level control on the cassette deck is turned down near the bottom of its range. But given your experience, and the fact that like your laptop Windows-based laptops commonly just have what is labelled as a mic input, and not a separate line-level input, I suspect that the gain and overload points of those inputs are not too different than those of the line-level inputs of separate audio components. I believe that the cheap electret mics which are commonly used with those inputs provide considerably higher output levels than most high quality mics, which would seem consistent with that suspicion.

A pet peeve I've had for some time is the lack of meaningful specifications for the analog audio ports on computers and computer sound cards, which generally makes it impossible to predict things like gain, level, and impedance mismatches with certainty.

Thanks again. Regards,
-- Al

Thanks very much for the responses, everyone! I will relay this info to my friend, and also possibly make use of it myself when I get the time!

I use a Nakamichi Dragon into an M-audio Delta 1010, running Steinberg Wavelab recording and mastering software. An M-audio Audiophile 194 sound card would be less expensive and almost as good. Unfortunately, many recent brand-name desktop computers lack an extra PCI slot. Aside from the playback cassette deck, the quality of your A/D converters will be the limiting factor. Unless you are a computer wizard, there is a steep learning curve to configure and learn to use this stuff.