Changes to the MAPI interface have caused problems when sending a file from the Windows desktop or a folder via "Sent to > Mail recipient" or via an external application like an office package, for example LibreOffice. To solve this problem, reinstall Thunderbird 60.5.2 from one of these locations:
https://www.thunderbird.net/en-US/thunderbird/all/
http://ftp.mozilla.org/pub/thunderbird/releases/60.5.2/win32/
http://ftp.mozilla.org/pub/thunderbird/releases/60.5.2/win64/(unsupported 64bit version).
Files with non-ASCII characters in their name also cause a malfunction. Two alternative workarounds exist:
- On Windows 10, set the system code page to UTF-8 (beta feature, see Region Settings, system locale)
- Reset this registry entry
HKLM\SOFTWARE\Clients\Mail\Mozilla Thunderbird - SupportUTF8 to 0