Thunderbird can't open links & files within a eMail and Firefox shows wrong Characters with the AltGr Key

Windows 10 Pro, Version 1909 (Build 18363.592)
Sandboxie 5.31.6 (64 Bit) and 5.33.1 (64-bit)
Firefox 72.0.2 (64-Bit)
Thunderbird 68.4.1 (64-Bit)

*** Without Sandbox everything works fine ***

I have trouble with Thunderbird and Firefox in the "Sandbox".  An upgrade from 5.31.6 to 5.33.1 did not solve the problem. Also a complete deinstallation including deleting the INI file and reinstalling (5.33.1) does not help. The only special feature in my system, I don't use standard profile folders for Firefox and Thunderbird. But the whole thing is stored as a path in the sandbox configuration.

Error description:

All characters, e.g. "@", which are called up with "AltGr" on the keyboard only work with "AltGr" + "Ctrl" + "Character". Example instead of "AltGr" + "@" i have to use "AltGr" + "Ctrl" + "@". If I don't do this, i get other characters in the browser, e.g. for a "@" I get a "q".

First error: When clicking on an internet link in an email the browser is not opened.
Second error: When opening a file in an e-mail, e.g. PDF, the file is not opened. I do not get an error message, nothing happens.

Has someone a hint for me?


  • +2 Same problem with Thunderbird here (on 2 different machines)!

  • In reply to wkfpv Koch:

    Thx - i had read this before. It seems at this time there more then one postings in this forum about the "not working links" with Thunderbird. But at this time i saw no solution. By the way the link in your answer does'nt work.


  • In reply to Thomas Weinreich:

    Thunderbird attachments now open again after updating Thunderbird to 68.4.2

  • In reply to wkfpv Koch:

    Yes, i can confirm this - attachements now open again with Thunderbird to 68.4.2 - thx for the hint.

    But it still remains:

    • Thunderbird can't open http links within a mail and
    • Firefox shows wrong characters with the AltGr Key: Workarround Keys is still "AltGr" + "Strg" + "Key" - for example "AltGr" + "Strg" + "@" shows "@" and "AltGr" + "@" shoes "q"