Hey guys, using Sonar X3 Producer (X3d build 278) x64 and I'm suddenly getting an error message every time I turn the program on saying that Soonar cannot open master.ins
 
I've looked it up and everywhere to simply turn on Sonar with SHIFT or CTRL+SHIFT and click OK, which I do... but it doesn't help. Any ideas?
 
Thank you!

Its possible its missing. Try a search on it. 

Hi. I would update to X3e.
https://www.cakewalk.com/Support/Knowledge-Base/2007013361/SONAR-X3e-Update
All the best.