Hi,
Having a problem with X3 that I've never had with any previous version. When opening a file, I get an error saying the midi device can't be opened because system is out of memory as reported by Windows.  It's just a standard MIDI cable/usb interface.  Never had a problem before X3.

Is X2a still installed? If so, does the file open properly in it?
Any more information about the file being opened?

It's a new file created in X3. X2 is installed, but I haven't tried opening in X2.  Like I said never had problem before, so the problem seems to be X3 related.

check for ghost midi devices in windows device manager?

lawp, can you elaborate?  Like I said, nothing is different in my setup except X3. So the problem seems to be X3 related. No midi devices other than what's always been there.

http://webcache.googleusercontent.com/search?q=cache:N2wIXbRID3MJ:www.harmonycentral.com/t5/Technology-Computers/Solving-the-Windows-MIDI-Port-Problem/ba-p/34667124+&cd=5&hl=en&ct=clnk&gl=us
 

this is what i was thinking of, but it looks like it's no longer an issue in win7:
http://www.cakewalk.com/Support/kb/reader.aspx/20090210
http://forum.cakewalk.com/Akai-MPK25-Midi-Issues-m2727261.aspx
http://answers.microsoft.com/en-us/windows/forum/windows_7-hardware/midi-device-limit/f2e746c7-9044-4cdf-9956-8fb700d479c9
http://forum.cakewalk.com/Is-the-MIDI-deviceport-limit-gone-in-windows-7-m1923991.aspx
in windows device manager, if you go to view --> show hidden devices, it also shows any hidden/old/ghost devices allowing you to delete them to be able to add more
 

Thank you Slartablartfast and lawp. Tons of devices in there after following Slartablartfast's link's instructions. Deleting now. Will report back.

Wow guys, thank you so much!!!!!!! X3 starts up and opens files about 10 times faster now--not exaggerating!
Had lots of ghosts in my house.  Had to do an exorcism.