Problem
Just joined fopnu and it looks good

My share folder works ok and if I search for something it shows up in Green so letting me know that the folder of mine is read and working ok.

Only one Problem ,whatever I pick out to Download it says in red:

Download Folder does not exist or, Error opening file for checking: The system cannot find the path specified (3)
 
Why ??? what is wrong, is it me or fopnu ?
Please can anyone help me ?

I've never encountered this issue, but my guess is your incoming files folder may not be a valid path or permissions on the folder may be causing an issue. if you have a secondary drive try creating a folder on it and set that as your incoming files folder.
the users folders on newer computers (my documents, my muck, my videos, etc) are virtual folders and may be causing permission issues.

This sounds like the incoming folder is either write protected or theres some other problem perhaps requiring administrator privileges ?

My suggestion is to create a new folder (something like "MyDownloads") on your root drive ( C: normally), right click on the folder and select properties to ensure the folder is NOT "read only" and then go into FOPNU settings and point it towards the newly created folder as the incoming files location.

Let us know if this fixes the problem or not.

An idea to ensure this problem can be flagged up to the user prior to it becoming a problem is to have FOPNU attempt to create a temporary file in the incoming files folder and do a simple rename as this can be used to flag up that the folder is not writable etc and the user can then see an error dlg/msg warning them the folder selected for downloading is non functional, a bool flag can be set if the error exists and can be reset when the folder is renamed prior to the test being undertaken again.

I know this sounds long winded but in software its a pretty small addition and may save  developer time in the future.