If you have imported it to cursor.cc, it probably is not a valid file, because there you can import images, not just cursors. It is probably a renamed png or something like that. You'll have to convert it to a real .cur file to publish it here, for example using the RealWorld Cursor Editor.
How do I publish a cursor
I want to publish a cursor
I wanted to publish a cursor so I went to cursor - upload then I filled out the form with a .cur file in the file section. But when I clicked upload at the top it said invalid or missing .cur or .ani file, even though my .cur file works, I imported it to cursor.cc and it worked, so it must be valid, and I don't know why this happens, please help.(This probably is really badly formatted because its my first time)