Which encoding is selected when that happens?

• Firefox > Web Developer > Character Encoding
• View > Character Encoding

Dear Sir,,, I have the problem only I received emails in Arabic and this problem appears only after I updated the browser, the problem disappear when I open the account on other browsers such as Internet Explorer attached a snap form the account

Try to set the Boolean pref gfx.font_rendering.directwrite.use_gdi_table_loading to false on the about:config page.

• http://kb.mozillazine.org/about:config

Start Firefox in Diagnose Firefox issues using Troubleshoot Mode to check if one of the extensions or if hardware acceleration is causing the problem (switch to the DEFAULT theme: Firefox/Tools > Add-ons > Appearance/Themes).

• Don't make any changes on the Safe mode start window.
• https://support.mozilla.org/kb/Safe+Mode

Try to disable hardware acceleration.

• Tools > Options > Advanced > General > Browsing: "Use hardware acceleration when available"

Dear Sir,, Thank you for your response, I tried the three steps or ways but nothing change. The problem still the same.

You did verify that the encoding is set to UTF-8?

• Firefox > Web Developer > Character Encoding
• View > Character Encoding

You can try to disable the website fonts temporarily as a test and choose some different default fonts to see if that helps.

• Tools > Options > Content : Fonts & Colors > Advanced > [ ] "Allow pages to choose their own fonts, instead of my selections above"

Dear Sir,, I tried the solution you suggested but nothing changed.

Do you get the correct characters if you select them with the mouse to the clipboard and paste them in a file in a text editor?

No, when I paste them in Notepad or Ms-Word they still appear as question marks.

If they are also appearing as ?? when pasted and the encoding is set to UTF-8 then I assume that the server is sending them as such and in that case you need to contact the site and ask them to look into this.

But when I open the email on other browsers such as Internet explorer they appear in letters not ????