How to change key binding for backward search in VIM?

Question

I am using VIM 7.2 remotely (in a server), and when I try to hit the question mark (in insert mode) it exits insert mode, and prompts for a backward search. In short, I can't type ? as plain text inside the edited file, even in insert mode.

The only available way to input ? in my computer is via RIGHT ALT+W key combination.

Thus, how can I change the key binding for backward search and release ? to be used as text?

It never happened to me in any VIM version I have ever used...

Thanks!

--

UPDATE: I discovered the source of the issue: it only happens when I am accessing the server via Windows terminal with OpenSSH. When accessing it from standard Ubuntu terminal, everything goes normal. There is actually no solution other than to access the server through other methods, as stated in the comments by @Heptite.