I bought it about 2 years ago!
For about half a year Minecraft always crashes, no matter which computer I play it!
Then I thought again: "Good come, probably can't play the old stored, because of any new compatibility problems…
Could it possibly be that you can only play Minecraft through this account for a certain amount of time?
And would you have to buy it again to continue playing it?!
Do you always play the same map?
If so, it is because.
With the same map surely mean "the created game"?
Um, well, yes, but I started a second one…
But that does not matter, because the second crashed the same way!
How can you actually fix this bug that it does not always crash?
Ever used another Java version?
You would have to know what's in the Crashreports.
Windows key + r
% Appdata%
.Minecraft
crash-report
Then the raussuchen with the latest date and best on pastebin.org or so upload.