[SOLVED] 2017.03 - Warning - all my vst-instruments are totally interchanged ...

Try a reset and rescan again. 

I have done a couple of vst reset and scans with 2017.3 and definitely did not have an issue with instruments changing.

I have done a "Reset" and tried to done a new scan.
But since a hour the scan is running in a loop. That means the dialog shows all second a plugin and after 1 minute it shows the same plugins again and again and again.
There must be a very mysterious mistake.
Now it's late at night (in germany) - and I'll go on tomorrow.

I don't think this is a thread-jack, because I have a similar issue. For me, it's mostly an annoyance. When I finish working on one project, close it, then open another without closing Sonar, I often have the same problem--the new synths I try to insert are replaced with something else. I was going to post here and ask if anyone else had this issue and then saw this thread.
 
I hope it's not a harbinger of worse things to come? Or perhaps a result of having too many plugins? I use Plugin Manager and have always created my own plug-in menu. Is that a factor, I wonder? Is whatever causing my problem also causing the OPs problem?
 
At any rate, it's only an annoyance for me. When I quit and restart Sonar and everything is fine again. It's just weird.

THambrecht
...Sometimes the computer doesn't react when I click "Scan". Then I closed SONAR, restartet the computer and then it does.
Now the instruments are in the right place.

 
Hmm...I don't know if you should be so quick to mark this thread solved because now your problem is starting to sound similar to mine. (I hope not! I hope you are all fixed!)
 
However, keep an eye on what happens when you work on one project, close it, then open another file without closing Sonar. That's when my VSTis start getting confused. Not on those that are already in that second project but any new ones I try to insert. Closing and reopening Sonar fixes it.
 

I would do a check of your file system with Ccleaner to see if there's any registry issues or general file corruption. It almost sounds like something to do with file integrity. Use whatever tools you're comfortable with but a little dusting and cleaning can go a long way.