Your browser is probably set to encode (print and display) text in a non-default way, probably Unicode (UTF-8). This can happen when fonts are missing or incomplete (especially in Unicode), or if software is installed that changes the default encoding for your browser.
If you do see question marks (or “funny” characters), you should be able to find them in the form, then delete and retype the character you want to see, then Save. The most common characters displaying this problem are quotation marks (single, double, left and right) and apostrophes.