Hello and hope you can help as this is becoming REALLY frustrating (lloked to see if another post about this but couldnt see anything)
Had Sonar since 5 and only seen this happening in last couple of X versions.
Anyway all recording, mixing etc functions fine (issues with some processing glitches, pops and CPU spikes but leave that till another time - doesnt happen while this is in play) - - go to export the total mix to a stereo file.........
Whether doing fast Bounce or letting run as real time render - - - randomly, and increasingly, only get a partial file printed (and what part can vary) .... and once done once on a track really hard for it not to happen again.
Tried diferrent names, fast bounce or real time render (with or without audio) - and nothing solves.
(oh and project and export at 48/24, selected Entire Mix, All or What Hear or Master Bus - happens on all).
I can go through 4 songs on a project all ok and then one will glitch - or can go through 1 and the nexct one glitches.
 
Anyone else with this issue? or preferably a solution - very very frustrating especially when working to a deadline or wanting a listening copy while travelling and need to leave for plane etc. Any help appreciated.
 
 
 

Try to select the tracks you want to export.Or do a ctrl-A to select all tracks.

Is it skipping time-wise (the same part of all tracks skipped) or track-wise (varying parts of varying tracks are skipped)?
If the latter, and you have MIDI softsynths on the tracks, you could try doubling the buffer at "MIDI buffers, prepare using xx ms buffers".
 
If  thats not the case, and random parts of the whole project are skipped in randomly chosen projects, then I don't know. I don't remember reading about such here.
Is there anything particularily in common with the projects that skip parts of export compared to the trouble free ones? A certain VST, Melodyne, whatever?

Once you've selected the tracks to export, scroll through the project to ensure that all of the seperate clips are selected.
Sometimes I find a clip that is orhaned during the selection.

Thanks for the assistance (sorrry didnt get notification there had been responses and been travelling)
Have selected tracks want to export and checked all clips selected
Usually it misses the first part of the track and does the rest - or does the start and stops at some point - its the total file not individual tracks.
There is nothing common with them - some have midi or virtual instruments  - others just live recordings.
Perplexing!!!
Kalle - If the latter, and you have MIDI softsynths on the tracks, you could try doubling the buffer at "MIDI buffers, prepare using xx ms buffers - - - -  where do I go for that, havent done that before (good to know/try and also for other times)
Anyway still unresolved

I always have used "select none" a few others here do the same. Seems to work better than select all which can miss stuff. 
Ctrl-Shift-A 
PS your in the wrong forum.