User-friendly links and file links problem

Can somebody please help me with the issue:
when trying to insert a link to file on the server where MODX evolution is installed,
MODX handles the link as if it was a user-friendly link referring to a page
and redirects me to the start page, as such page alies doesn’t exist...

For example, http://www.mydomain.com/files/sw80/document.pdf

How do I avoid this, maybe it’s an .htaccess issue.

Thank you!

It will do this if the file or its directory do not have the correct permissions. I had mine at 660 for files (my old server used these permissions) and had this problem; setting to 664 or 644 solved the problem.

Thank you!
Changing permissions helped!