Cyrillic suddenly turning into question marks

I've made an application which shows cyrillic text, but all of a sudden all the cyrillic turned into question mark signs inside a squared box. This has nothing to do with my script, as I开发者_如何转开发 checked my backup which is working and it was just the same there. Can it be something with my browser? I've tried to restart it. I'm using Chrome.

Are you using a meta tag that sets a charset?

It looks as if the Cyrillic alphabet uses utf-8.

http://webdesign.about.com/od/localization/l/blhtmlcodes-ru.htm