I just re installed Pro because I had deleted it and lost LP 64 MB. So I re installed it no problems. I didn't get my LP 64 back so had to install X3 again too. Lesson learned, don't un install your old versions if everything is working. 
 
I originally upgraded from X3 Studio to Professional. I'd still be with it and happy but was suckered in by a very good upgrade price point to Plat. I often accidentally opened files in Pro and it would take a good long time to realise this had happened.  
I really don't use the extra features you get with Plat, as a matter of fact I get buy pretty good on my new system with Home Studio. 
So if your install failed you either had a corrupted download our your system itself is un stable. 
 
Oh dear, I see your using a Lexicon omega for an interface... 

CACTUS: I am beginning to have my doubts about my ancient Lexicon Omega. It did OK when my mixes were simple. But now its unsupported ASIO driver appears to be designed to drive me nuts.
 
ABACAB: Good idea. 
There was a stack of about 6-8 of the following errors, with a different DLL for each. I did not record the names of each DLL.
 

 
This finally resulted in the program aborting at launch with:
 

I'v been using Sonar Professional for a year now, at first I was getting bluescreen issues when editing midi parts. Now I never had an issue with it probably since the last 4 months or so. Btw, I'm using Windows 10.

Edit: The audio engine randomly crash, like ones or twice in an 8 hour recording and mixing session. I still have that problem even with the latest update.

guyshomenet
CACTUS: I am beginning to have my doubts about my ancient Lexicon Omega. It did OK when my mixes were simple. But now its unsupported ASIO driver appears to be designed to drive me nuts.
 
ABACAB: Good idea. 
There was a stack of about 6-8 of the following errors, with a different DLL for each. I did not record the names of each DLL.
 

 
This finally resulted in the program aborting at launch with:
 

I think scook must be psychic, or something.  He posted his link above regarding your error before you even replied!
 
Please try the solution he recommended, and let us know how things worked out.
 
The Visual C++ Redistributable Packages install run-time components that are required to run C++ applications built using Visual Studio 2015.

When I was using Professional back in 2015, I was still on W7 and then I built my latest Daw listed below and bought W 8.1 because it was cheaper than W7. I had blue screens up the ying yang. I thought I was a failure at building computers..
But that as it was, due to a faulty power supply. Brand new but buggered. Fixed the power supply and haven't had a blue screen since. Just saying, blue screens should not be software but hardware related. So my run with Professional was smooth sailing and I had that computer on for sometimes 16 hours. 
 
Ya when I saw your Lexicon a red flag went up. Been a few folks coming here with issues with the drivers for those. I have the Lexicon MX 200 and they haven't updated the drivers since XP 32 bit even though they still sell them brand new?? . Defiantly on my mental short list of interfaces to avoid. 
 
Have you run all the updates for W7? Sounds like your missing one of the MS Visual C++ things, on my W7 laptop there is 17 of em.. latest looks like # 14.0.24215
There are issues with W7 updating properly these days and you might have to manually download and install them. Go to the MS W7 support pages. There's a list of updates.
Sonar is becoming iffy with W7 support, don't blame them it's a PITA to waste manpower bug hunting as it is without having to bug hunt in old OS code. 
 
You can still upgrade to W10 for free. I just did. As long as you have a legit W7 serial number they will let you upgrade if you use Assistive  technologies. like the magnifier. 
 
https://www.microsoft.com/en-ca/accessibility/windows10upgrade
 
 

Well, this is embarrassing. 
 
I was once an IT guru. Ran big iron for NASA, then for a national retailer before going over to the Dark Side (tech marketing). So something like updates should be top-of-mind.
 
When I bought the DAW box from a local gamer, he said he had laid down a fresh Win7 install (clean install ... no remnants of anything) and that he had updated the OS. I trusted him.
 
Trust, but verify. I forgot that last bit.
 
So I looked at the OS per suggestions above, and not only were there few updates installed, SP1 had not even been installed. Sweet Jesus, no wonder X2 was doing quirky stuff.
 
Anyway, the short of it is that after a few hours of updating the box, not only did the demo of Producer install, but a lot of the latency issues I was having with X2 dissipated. I'm now debating if I should bother test driving Professional.
 
In that regard, I have some questions for you very helpful folk:
 
1) Win7 or Win10 under Professional?
 
2) Is Professional better enough to justify the cost for someone cutting demos and doing mild distance collaborations?
 
3) Assuming the Lexicon Omega is finally identified as burdensome, what modern interface (2+ audio and MIDI inputs, plus RCA outs) would you recommend, assuming it has a modern and usable ASIO driver?

I would answer to # 1 and # 2 like this:
 
1. I think that Windows 10 is where the Sonar development focus will be moving forward.  I still run one Windows 7 box, but realize that MS update support will expire in 3 years. 
 
2. I think that Sonar Home Studio at $49 is probably sufficient for that.  But Professional and Platinum offer many FX and instruments that are useful if you are starting from scratch.  The core program is the same.  Artist for $99 may provide a better upgrade path if you are not sure.