How to unsync files and folders

[menk]

Hi I changed my downloads location from desktop to H drive for usb and now the problem is the desktop folder is in sync with my usb. In the process of changing the location (right click the download folder and select properties and select the "Location" tab), a pop up says that more customizing is needed with Firefox but not IE, and it was also saying if I would accept desktop files and folders to be moved. I clicked ok and the desktop items have been replaced by those from my usb, without customizing Firefox then. How can I un-sync them and get back my desktop function? menk