I've seen various weird stuff happen with synths after they've been turned off for a while in the synth rack and then turned back on at a later date. Many times Sonar has reloaded the synth with some aspect of the preset screwed up. This one takes the cake though - I just turned on an instance of Kontakt with Strummed Acoustic loaded to go back and reconfigure the sound. This is what I was greeted with: 
 

 
It's completely screwed and does not work at all. Anyone else seen this with Kontakt in Sonar? 
 
Now the sound I had is totally gone. Cheers Sonar me old pal 

?
Had a party tonight till 4am and it was the old addictive Keys, AD drums and Kontakt vintage keys. No issues whatsoever..

On Studio One.

Hi Sharke,
 
That's a new one on me, and I use Kontakt quite a bit and for many years now. Although, I play guitar so I don't use Session Guitar, so that could be a factor.  Have you seen it with other libraries/instruments?
 
The way you describe it, sounds like it could be some sort of temp file corruption?

I play guitar too but I've never been able to eliminate fan noise from my recordings sufficiently for my tastes. Shame, I have some good mics. 
 
I haven't seen this with other instruments, and in fact I haven't seen it with Strummed Acoustic either. I have however had problems with "waking up" sleeping synths in the synth rack before. I don't know what Sonar does to them when you turn them off (or back on) but there is definitely something going on there. I've heard other people say they've had problems with synth settings being destroyed or vandalized when they've turned them back on. 

Sounds pretty bizarre.  I wonder what the factor is that makes it happen to some people and not others?  Win 10 v 7?  Intel v. AMD? Phase of the moon?  Software can drive you crazy sometimes!
 
Luckily, these don't do that to me...
 

 
 

Who knows. But I have some large projects I really need to finish in Sonar and a plethora of annoying crap like this is really making it difficult. 

I've never seen this on my system and I often use NI Strummed Acoustic (versions 1 & 2)  to lay down temporary backing tracks prior to getting a vocalist in. This is useful as I can instantly transpose the part if needed.
 
Saying that, I don't usually switch Kontakt off in the synth rack. I'll give it a try later today and see if I can recreate the issue.
 
 

You have to switch the interface language all the way from Martian to English.  Looks like you have the dial only about half-way.

I've recently seen this type of behavior with Stylus RMX too, the graphics get all messed up. Only happens in Sonar!
 

I always freeze rather than turn off synths (don't know if that actually makes any difference, it's just what I do).
 
The only issue that seems to occur with that particular synth is that the sound preset seems to always revert to it's default when unfrozen, so I have to remember to re-select the sound it should be before re-freezing. I've never used it that much so always assumed that it was something I was doing wrong as I've never seen it happen with any other synth other than the odd demo, which are crippled deliberately.
 
Stating the obvious maybe, but sometimes we all overlook the obvious, does this also happen in your back up copy?