MC4 Reinstalled - new problems

Did you save the old stuff in MC on the new hard drive, close MC, re-open it then try exporting?
 

In MC under Options>Audio, what is listed for playback device and recording device?

Did you use the export preset "WHAT YOU HEAR" as the option in the drop down box that opens to export the project? It's in the same box where you select the 44.1/16 settings.

If it sounds fine in playback it should export that way as well.

I had never noticed  "What You Hear" before in that drop down box. I have never used any of the presets before when exporting. Should I?

What I am usually doing is creating individual practice tracks for a chorus. I am generally exporting two audio tracks at the same time. One is a vocal track I recorded directly into MC4 via a microphone plugged directly into my soundcard. The other is the accompaniment track which I create in Finale and either import as a WAV if I want to use my Garritan sounds or a MIDI file if I want to tweak the tempo changes, etc. in MC. Then, of course, if it's a MIDI, I record it over to an audio track. I usually create a full mix with all of the vocal tracks plus the instrumentals.

After trying a bunch of other things, I wound up fixing the problem by shutting everything down again, restarting again, and making very sure I was clicking all of the right settings. I'm glad it's working now, but I'd love to know what went wrong. Since I have no idea what fixed it, I guess I'm just hoping it doesn't happen again....

So...if I'm not using any FX or envelopes, does it matter if I use "What You Hear"? I'm just wondering what, specifically, that selection will do to change my end product since I've never messed with it. And everything on the right hand side is selected - Track Mute/Solo, Fast Bounce, Bus Mute/Solo - everything. I've never messed with any of that either, just left them all at the default setting.

No, I don't want to select all of the tracks. I am only exporting certain tracks on purpose. The idea is that each of the sections of the chorus gets a CD with just their vocal part and the piano part for each song, but not the other vocal parts. It makes it easier for them to rehearse their part at home without being confused by the other harmonies. Then I also sometimes do a full mix with all of the vocal parts so that they can hear their part in context. I've been making practice tracks like this for years with pretty minimal problems (going way back to plain old Cakewalk!)  The problem this time was with the actual quality of the audio I exported - despite how it sounded in MC4, it sounded very tinny and low quality in the WAV or MP3 files that I was exporting. Still stumped.

You can try What You Hear anyway; what can it hurt? And it may sound better. Make sure the track you're exporting is selected (the clips(s) will turn black), then choose the preset.
It seems something went goofy when you installed the hard drive. What that is, well, who knows?
You can also check your sound card settings. Some have a default effect, like reverb, that will also export, though why you don't hear it when playing the track...
Anyway, something to look at.

Reported the whiner as a spammer, and blocked it.