Noel Borthwick [Cakewalk]
By any chance are you using UWP mode with an offline bluetooth MIDI device selected in MIDI preferences?
Does SONAR work ok if there is no project opened?
SONAR does work properly by itself. I can make music, i can edit stuff, midi is working properly (not using UWP btw) and i can use and save template files.
I've tried rolling back to 2017.03 (from 2017.04, clean install), 2017.02 and 2017.01. I've also tried a clean SONAR install of the version 2017.03, 2017.04 and 2017.05.
I am using the UR28M (latest drivers and i used it earlier with SONAR), latest component drivers and the HDD to save the files on, is working properly. I've tried other HDD's (2 other data HDD's) as well. I don't use the onboard graphicscard and soundcard (both are disabled).
I use (and tested) other DAW's as well (FL Studio, Ableton, Reaper, ReNoise) and they can save and reopen project files just fine on those HDD's.
I've tried "safe mode", but this didn't do the trick either.
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It is sooo weird. I started a track, saving it as a template file (so, with vst's and vsti's) and it opens (menu->new->template) perfectly...So (and this is really annoying) there is a workaround. I can start a track and save it as a template for the time being. Pffff...annoying.