qBittorrent official forums

I am getting this error message when using qBittorrent with a specfific private tracker: Is this a problem with qBittorrent or could it be an issue specific to the private tracker?

I get the same results on both Windows and Linux, and on the same Linux computer I am able to successfully download from the same private tracker using Transmission instead.

Any ideas?

The site in question probably uses either a blacklist or whitelist to control what client you use, most likely they also have a list of acceptable clients, ask them if or why it's not allowed and if they would allow it, which they should. Or else it's time to find a new private tracker.