I installed impro-visor and that did not magically fix the problem -- but it does have a midi preferences tab and I went on there and the M-Audio shows "undefined external error" and all the others show ready to use -- maybe my M-audio usb to midi adapter has crapped out?

I again plugged the alesis IO2 plug and play interface -- and it also gives the "undefined external error" message in impro - visor.  Now as I said, the audio side of the of the IO2 is not working so it might not be safe to assume that the midi side works.
 

Alright, I installed improvisor on another machine we have here and plugged in the plug and play alesis IO2 and it shows up as "ready to use" on that PC so I am pretty sure that interface works -- so it still appears that i have a windows/PC problem -- I sure hate to go through a reformat -- gonna put that off a while longer I think

A complete Windows re-install may solve the problem, but if it does, the problem probably could be much more easily solved. Before messing with Windows, it would be a good idea to isolate the problem. As you note the MIDI interface is not malfunctioning if it works on another computer, so it must be a driver, application, or setting issue. If anything (thumb drive, mouse etc.) will work on your troublesome computer in the same USB sockets then you can be pretty sure that Windows is recognizing USB there. The easiest thing to try is to delete the Uno driver on the computer where the interface is not working, and then re-install the driver there. Check to make sure you use the latest driver available for your version of Windows when you reinstall it. http://www.m-audio.com/support/download/drivers/midisport-windows-driver-v6.1.2 If you are stil not getting it to work, the next test is to bypass the guitar studio application to be sure that the Midisport works under Windows. Download MidiOx http://www.midiox.com/  and install it. MidiOx will give you the option to use your MidiSport as a MIDI input. You can then check any output from your MIDI controller to the Uno to be sure it is transmitting correctly. If the interface works with MidiOx  then there may be a problem with the application or application settings. A simple thing to try is just uninstall and re-install the application.
 

thanks so much Slartabartfast -- a lot of that I have tried -- I have uninstalled and reinstalled the UNO driver several times but I have used 6.1.3 am I missing something?  Is that one not right for me?
 
The other problem I have is I cant uninstall cakewalk -- when I try it says such and such of file cant be found by the unistaller  -- I'm not gonna do a reformat any time soon, when I can I will try midiox -- a rollerskating mishap landed me in the emergency room last night with a dislocated elbow along with other torn up stuff in there -- so for the moment I am kind of dead in the water and typing one handed  - thanks abunch for the help

As a general rule when an uninstall fails, the best thing to try is to install the program over again, that will generally restore the missing files needed to uninstall the original version. You may get a message that the application is already installed, but if you have an option to override it do so. Another option is to try Revo Uninstaller free.
http://www.revouninstaller.com/revo_uninstaller_free_download.html
 
If you do get it removed, and try to install it again do the installation as a "run as administrator." http://www.7tutorials.com/how-run-programs-administrator-windows-7
 

I forgot to say that yes my usb mouse works in all 3 usb inputs
 
This is a really archaic version of cakewalk from circa 1999, I have tried reinstalling it on top of the old installation but it comes to the point where it says installshield is trying to do something and then it disappears a couple minutes later.
 
I left a slip of paper with notes in the jewel case telling how I finally got it installed the first time -- gotta run as administrator in compatibility mode for windows 98 -- then when it says its gonna reboot to complete the installation you choose no and it goes to the cd key registry stuff then you reboot it later  -- if you let it reboot when it wants to it just comes back up smiling with nothing ging on as if the reboot was not part of any installation.
 
I realize this is ridiculously old and I will have to update, but I get the feeling that no midi is going to work via usb right now which seems to point back to the original suggestion that hidden devices have crowded out the midi ports  - maybe I uninstalled them wrong  -- and what about this default midi device stuff?  Could that possibly help me if I could get the midi uno designated as the default device?

I may try the revo but not just yet
 

It seems more likely that your old software is not able to connect to a contemporary MIDI device in a new OS than that the MIDI device is not working in Windows 7. That is the point of trying to use another application to test it. If MidiOx can interact with it, you can stop worrying about a problem with Windows and MIDI or your MIDI interface. The only way that hidden MIDI devices would have become a problem is if you had installed a lot of MIDI devices on that same Windows installation in the past, and never deleted any of them.

well it worked for a long time until I did a manual PC cleanup about a month ago, and if its plugged in it still shows up in midi devices in the old cakewalk but if you try to choose it then it balks, and when I try to run that app "Impro-Visor"  the m-audio uno shows up but has a status of "undefined external error" as does my other usb midi interface