Unable to load match because of critical error

I was unable to load into an ARAM match because of a critical error. Logged out several times and back in and receive the same error message. The clients showed I was in a game even though I could not connect. My status cleared up after the match ended - unfortunately my team had to surrender.

Same issue when I queued again. Here is the message:

System Error A critical error has occurred and the process must be terminated.

Would you like to create a crash dump to aid the developers in troubleshooting this issue? This may take up to 5 minutes

NOTE: The process may appear unresponsive during this time.