I see that I can delete networks that my machine "remembers" from nm-applet by clicking on the wireless icon in the panel and selecting "edit connections" -> "wireless". However, sometimes I click on the wrong wireless connection by accident in the dropdown list. If the connection is secure, the machine of course never successfully connects, but somehow it still seems to memorize the ESSID. Whenever I'm in range of that wireless, it now tries to connect.

Worse, if not connected to any other network, it repeatedly prompts me to connect to this network. If left unattended, I may find dozens of copies of the window prompting me to log in to this mistaken network. There must be a file somewhere that records this connection ID, but I cannot find it. The only connections appearing in the "edit connections" I mention above are those to which I've actually connected. How do I find the file and delete the line corresponding to the offending "memorized" network?