Cant download

We need a lot more info about what exactly you are trying to download on what system using what method. As Ravi explained, this error usually comes up with orphaned instances of the download manager or similar, but without knowing the specifics, nobody can realyl tell you how to avoid the issue.

Mylenium

What browser are you using? What software are you trying to download?

The error message usually comes up when you are trying to run more than two instances of Flash Player installers simultaneously.

Make sure the software you are trying to download has not another instance running, i.e. you are trying to downloading again while an existing download of the same is in process

Click OK to the message that appeared. One of the installers gets closed and the other installer continues automatically.