Telethon 'download_media' downloads all files apart from 7z which are always corupt

[githubuser422]

Code that causes the issue

file_path = await client.download_media(event.message, download_folder)

Expected behavior

I have a very basic download script that sits there watching for any posts in any channel my profile has joined. If the post contains and media etc, the script downloads to the download location specified.

Actual behavior

The script works as it should apart from where the file to download is a 7z in which the file gets downloaded, appears to be of the right size but is always corrupt (ERRORS: Unexpected end of archive). All other files download without a problem, including other archives (zip, tar etc)

Traceback

There are no errors provided - telethon appears to download the file

Telethon version

1.38.1

Python version

3.12.3

Operating system (including distribution name and version)

Ubuntu 24.04.2 LTS

Other details

No response

Checklist

• [x] The error is in the library's code, and not in my own.
• [x] I have searched for this issue before posting it and there isn't an open duplicate.
• [x] I ran pip install -U https://github.com/LonamiWebs/Telethon/archive/v1.zip and triggered the bug in the latest version.

[Lonami]

Telethon doesn't care what the files are. I'll need access to a faulty file before I have any chance at fixing this at https://t.me/Lonami (please link this issue so I know who you are).

[githubuser422]

Yup - I know Telethon doesn't care thats what has been bugging me over the last week or so this has been happening! It has been working in the past as well and its been the last few weeks - not sure if there is anything new on Telegrams side that would mess with 7z even. Will get one across to you as soon as I can.