I have a problem. I have created a project on X2 Producer, and it has been a work in progress for months now. Suddenly, it freezes X2 after loading when I try to press the play button. I eventually reinstalled X2 with the same result.
 
Desperate to not lose my work, I loaded up my old version of Sonar, (7) which doesnt officially run on Windows 7, and the project plays. I resaved it under a different file name and the newly saved file has the same effect on X2. - it hangs.
 
I thought it could be a VST effect that I am using that is native to X2 and doesnt run on 7 that may be the cause, but rather than go through every VST in safe mode start (there are a lot of them) I wondered if anyone had any other ideas?
 
Core i5, quad, 4 Meg Ram Win 7 Edirol UA-25

When the project hangs in X2 is the audio engine still running? Could it be that the project is not hanging but is dropping out.

Try saving a new version of it and see if that opens it. If not, its a plugin and you will need to open it in safe mode to see what plugin is causing it. sure it takes time, but if you want to solve it, then you need to take the time to do it.
 
Also, Is it 32bit or 64bit? Sonar 7 and Sonar X2.
Have you installed all the X2 patches?
 
CJ

You can narrow it down by bypassing all effects as a test, and if it stops hanging you will KNOW then that it is indeed one of your effects.
 
To test it, load the project, then hit the 'E' key on your computer keyboard.  This toggles off/on the Bypass All Effects functionality in Sonar.  After testing, you can turn them back on by hitting 'E' again, or by closing the project without saving.
 
Bob Bone
 

@ Scook Thanks, the audio engine is still running
@CJ, I did try save it under a new name, but with no luck, Also I am using X2 and & 7 32 bit versions. I have only loaded this patch:
 
 are there more?
 
Yes I thought I would have to try the safe mode approach.
 
@ Bob, thanks for this tip, I did not know about it and will try it
 
 

If you're comparing the 32Bit version of Sonar 7 vs. the 64Bit version of Sonar X2, the issue is almost surely a bridged 32Bit plugin.

If you're using the 32Bit version of X2, are you running out of RAM (limited to 4GB)?