I was working on some basic Fire Particle system in the Cascade editor and had to Undo a few times to get back to a certain result. But as I did Ctrl+Z a few times together, UE4 hung up for a couple of minutes and then crashed. It gave a crash report:
"To try and fix the problem, Windows has applied compatibility settings to this program. Windows will use these settings the next time you run the program.
If you noticed that this program didn’t run correctly, try running the program again."
I was using 3 Emitters and 3 Materials in total. I did not try that again, because it crashed all the task I was working on 
Hi Shashank,
Can you please tell us the name of your Project? This will help us to track down the crash report.
Also, if you have the log from the project when it crashed, it would be helpful if you could attach the file here.
Thanks
Hi Stephen,
The last time I did it, my internet was not working at all, and I did not save the new project too. But just now I have recreated the problem. Only this time, before crashing it opened a Log dialog box and gave a long error. You can find it attached. My Project is called “Test01”.link text
Cheers!
Additional Information:
Again, I had done the Undo a few times throughout while making the Fire Particle, but when I did a few Undo’s after creating 3 Emitters, it crashed.
Each Emitter had a separate Material, whereas each Material had the Particle Color node multiplied to its Emissive as well as Alpha Channels. Also, Each emitter was using the Alpha Over Life and Color Over Life actively.
Hope this helps 
I have tested this in a particle system with multiple emitters and multiple materials, and I have still not been able to reproduce the crash.
If you are able to determine the exact steps that can help us to reproduce this issue, please do not hesitate to let us know.
Thanks
Hi Stephen,
Unfortunately somehow today when I tried to reproduce the crash yet again, it did not happen at all, even though I did everything I could recall from the last 2 times, including changing Textures randomly in the Materials I had applied to the Emitters.
On the other hand, were you able to track down the project and the crash or was the Crash Report I attached any use?
Cheers!
Unfortunately I have not been able to locate your crash-report in our records. Delivery of the reports may be blocked on your system, or our service may have been down at the time. Additionally, the CallStack you were given does not provide enough information for us to work with (this is expected).
Just be sure to let us know if you crash again or determine the repro steps.
Thanks
Hi Stephen,
I couple of days back the same error log came up and then crashed while I was trying something on Blueprints. At that time I was just trying some nodes, and no Undo’s or anything.
Do you think it could be a problem with memory or something? Although I have a pretty good configuration.
Please let us know your system specs. It is certainly worth consideration.
Thanks
Intel i5 3.20 GHz, 8GB RAM, GTX 550Ti 1 GB.
You meet a combination of our minimum and recommended settings, so the possibility of it being a hardware issue exists, but it is not the most likely cause.
If you are able to determine the steps to cause the crash which we could reproduce, please let us know.
Cheers