Wrong encoding in the name of the Russian attachment

Wrong codepage in name Russian attachment. All emails with such an encoding were sent from Outlook 2003. Changing the language in the settings did not produce results. Please help me.

Hello Nikita,
do I understand correctly that if you send a russian attachment to yourself or anyone from eM Client this issue doesn’t happen? If so, it could either be Outlook sending out the encoding already as corrupted or it could be changed on the server.
If you can replicate this or resend these attachments to me (rust@emclient.com) I can have a look at the email source, but it is possible that eM Client already receives these filenames as corrupted and therefor cannot view them correctly.

Best regards,
Olivia