Internal Server Error - Cannot Access Files

Nextcloud version (eg, 10.0.2): 12.02
Operating system and version (eg, Ubuntu 16.04): Ubuntu 14.04
Apache or nginx version (eg, Apache 2.4.25): Apache

The issue you are facing:

13/09/2017 18:55:11, file1.pdf, Nextcloud,Error downloading https://vps/nextcloud/remote.php/dav/files/path/to/files/file1.pdf - server replied: Internal Server Error

I really need these files for university work. What’s that error mean and how can I resolve it quickly please? Rebooting my VPS hasn’t worked.

how do you try to access this file?

Through the Nextcloud client.

ios? android? windows? linux?

Error appears on a single Linux client. File isn’t there on other Linux, Android or Windows clients. Tried doing occ scan:files all (or something like that, the server did the scan).

why not trying to access it via nc-gui directly? you could try and share it external

Excellent idea, unfortunately I get following issue:
PDF.js v1.4.20 (build: b15f335)
Message: Unexpected server response (0) while retrieving PDF “https://vps/nextcloud/remote.php/webdav/path/to/file/file1.pdf”.