1.7.10 crashing

i was on Minecraft 1.7.10 on my dad's Desktop. i tried to connect to a 1.7.10 Pixelmon server, but then Minecraft crashes. Every time i try to join that server, it crashes, If im on my dad's Desktop it crashes, but if i try to join the same server but on my laptop, it does not crash.

and on Affects Version/s there is no 1.7, so i did 1.8