When I install maxthon_portable_7.5.2.4600_beta_x64, Maxthon opens. So there's no problem with the portable version.
However, when I overwrite the portable version with my old "User Data" and "Resources" folders, Maxthon seems to open but closes after 3 seconds. I suspect the error lies in these two folders.
But as I said, I don't want to use the portable version. I want to fix the problem.