If it's more than one project, it would seem unlikely to be a corrupt project file. If it were, you could save the entire project as a new project and probably cure the problem.

More likely, it's a particular synth that's not initializing when you open the project. SONAR thinks it's not there anymore and the envelopes' links to it are no longer valid. Hence the orphaned envelopes. Maybe you're using a demo version of some synth, or one that's not installed properly?

Orphaned envelopes can be deleted by opening the project in 8.5.3  

Since you don't have 8.5 on that system you can still delete any in X1.

bit,

That's actually something I didn't consider (un-initialized synths.) I'll keep that in mind and see what I can find next time it happens.

Thanks again for all the help, everyone!

I think I had something similar happening to me recently. In my situation, I had an effect plugin with automation that I decided I didn't need. When I deleted the plugin from the effects bin, the envelope stuck around and I had behavior similar to what you're describing (though it's been awhile and I can't recall if it was exactly the same issue). Fortunately, it was just the one envelope, so I was able to recall which plugin I used: re-inserting and enabling the plugin let me have access to the envelope normally again, so I deleted it and then got rid of the effect and the problem was gone. Hope that helps you a little bit.

OLD THREAD, but I have the same problem (x1).  The synth is not deleted or invalid (FM8), it plays fine.  The behavior is EXACTLY as the original poster described.  The envelopes do not show up in the envelope assign list (they are there, but no colored dot by them, when I click on them, a new envelope is created.  Right clicking does not work, shift clicking does not work.  They are, as the original poster suggested, unreachable.  Has this been fixed in x2 or x3?

There will be a demo soon...

i have the same problema and is not fixed in the X3d update.
I have a temporal solution:
Select the track where you have the orphaned envelope.
Go to view menu and select the Event List, there you can see details of the orphan envelope and remove it.
 
 
Sorry for my english.
 

In the "read me" for X3d, in the section on Backwards Compatibility there's mention of a problem with disappearing envelopes when opening an X-series project in a pre-X-series version. I was going to suggest opening in the version that created the file, selecting "show all envelopes," re-saving under a different name, and seeing what happened...

"View event list" doesn't work for me:  all I see are note events, no envelope events.
If I clone the track, the orphaned envelopes disappear, but the single-track synth gets split into two tracks.  When I try to pack it into one track, I get an error message that "instrument tracks must be sent to a single output" (or something like that).
I just solved the problem by creating a new instrument track and copying the data from the bad track to the new one. Then delete the old track.  The orphaned envelopes did not copy.