Uploading concerns

Hello! I recently had a 30-day trial with BulletProof FTP, and it just ended. So, I began to search for others to download and found several. I tried to upload to my site, and it wouldn’t work- I was logged in and everything. So I downloaded another program, and it would say that something had been edited on the program, but would not upload currently to the site. Thanks! If anyone has any ideas of why this might occur, please reply!

God Bless You!!