But no window will pop up if you've already clicked previously "always use this answer" & clicked no to downloading it. Follow the directions in the link birdy gave.

As a last resort, you could try deleting your LW Preferences folder whilst LW is closed; instructions here: Point #2 & 3 in Fixes for Limewire (sample image included at bottom of page.) But before you do that, make a note of any important settings such as where your download folder is, where shared folders are, etc. under the Tools>Options menu bar. Next time you open LW you would need to reset everything as though you were opening the program for the 1st time. (But your previous downloads/incomplete files will still be there so long as you choose the same downld location.)

Oh I must be a slow typer ... I didn't see WW's response above.