SD Card mounts, but cannot be read.

Trying to explain this the best I can...
My origional Droid running Project Elite 4.2 has an SDcard that's 16GB. I've used down to 2GB with 1,200 songs and countless pictures as well as a few apps that can be moved to SDcard.
I've had this phone for a year, and the PE4 since the end of December, and never had an SDcard problem. Today my alarm went off but not with the usual Korn "Wake Up" song I have saved on the SDcard. It was just a normal default system sound. I checked my ringtones and all my music was gone! Every ringtone I created was gone! The Tone Picker said "No Music Or SD Card Inserted." So I turned on the PowerAMP had no music in the song list. 1,200 songs...gone. I then noticed that in Gallery, all my pictures were gone.
Here's the kicker, my SDcard is still there, mounted. My apps still work perfectly. I can go into Root Explorer and manually play my songs and look at pics. Yet my apps are not seeing these songs and pictures. I also noticed that I can still take pictures, and save them to the SDcard. And they even show up in Gallery. But how come my old pics are not!? I also downloaded a new song using MP3 Downloader. The new song shows up in PowerAMP, but the old ones do not.
Any ideas? I'm gonna try to copy my SDcard to a computer and re-format, but I need a 2.0 USB port or it will take forever.

Sorry that this reply is so late. You _might_ be able to alleviate the situation by taking out your sdcard and gently cleaning the contacts with a toothbrush and/or just reseat the card and try from there.

Otherwise, I would suggest what you started, copy everything to your pc, reformat the card with the phone and xfer back. Or better, get a new card and _then_ xfer back.

good luck

I transferred to my CPU then reformatted my sd card and transferred it all back. It worked for about an hour and quit reading again. i checked for viruses and errors and something was wrong with my wireless Tether. I deleted the app, but think I gotta do it again

Try another card. If you have the same problem then you have a faulty SD card interface. If the problem discontinues then you have a flaky SD card and will need to replace it.

Ok, this thing is nutz. I'm now starting to think it's not the SDcard in general. My WiFi decided not to work anymore. My home WiFi is working perfectly, yet my phone is not connecting to it while my PS3 and my wife's HTC Incred are both connected with no problems. My phone is saying "Connecting"..."Disconnecting"..."Scanning"..."Con necting"...ect.
I found this out yesterday. I've tried different Roms from Bugless Beast to Ultimate Droid. I've also did complete wipes of my phone's cache & data. It continues to do this.
I'm outta options now.

Delete all stored hotspots and then try again. If that doesn't fix it then try resetting the router.

Also, Droid 1s do NOT like one kind of encryption, so if you're running encrypted you should swap the encryption type or just broadcast in the clear.

I did both. I realized that while I was disconnected from the router, my phone "Scanning" for 2 seconds then stopped for 5. Then it would say "Scanning" again. When I told it to connect to my router, it would "Connecting" "Disconnecting" "Scanning" loop again. It's like it wants to keep scanning and scanning for no apparent reason. I looked for a way to stop it, but I don't know how.

I really appreciate all the help you guys, but I think my phone is killing itself.

Here's a big hint. When a buddy tells you he's gonna overclock/underclock your phone for performance & battery life, make sure he's not doing it the same way he did it for his Droid X.

My OG Droid died. Insides completely fried. My SDcard is inside my new HTC Incredible, but still having the same problem, thus my SDcard is probably fried too, even though I can still use it to Root my Incred, and re-install all of my apps.

Sorry you lost your D1. I hope the burial was appropriate. :)

Replacement class 2 SD cards aren't that expensive -- however, if you want to bump up in speed you'll start paying a lot more in a big hurry.