Hello. I have had a problem that has happened today. It is about Optifine. I have been using it for months now, and has worked perfectly. Now, it does not. This problem occurred when I was changing the screen resolution to play around with things. When I tried F11'ing to save the changes, my Minecraft crashed. I just thought I could re-open the game, but when I did that it crashed again. So, I repeatedly did this for like 5 minutes until I realized that it could be a problem with Optifine. So I went on regular 1.8/1.7 and it worked fine. I have tried System Restore on my PC and that still doesn't work (i set it back to February 24th but I think that hardly matters.) And, if this means anything, the client of Minecraft keeps trying to open before it crashes, and it makes a black screen flicker but it does not open. It just stops flickering, then a few seconds later the "Crash Report" thing comes up. If anyone can help me with this, thank you very much.