I've discovered a little more about the "Invalid Request" message. Whilst I suggested this was previously known to happen when the upload file has been removed from the shared folder since after beginning the LW session, this is also true, I tested it. The files that seem to get that message in general seem to be incomplete files. With so many shares I didn't notice until now. LW 5.5 & I'm guessing the earlier LW 5 versions also, had no user control over whether incomplete files were shared using the partial-file-sharing technique. Partial-file-sharing is done by default in LW 5. In LW 4, the user had a choice whether to allow partial-file-sharing or not. Partial-file-sharing is where you share parts of the file as you are downloading the file. Much of the file transfers on the gnutella network is done via this technique. Torrents also use this same partial file sharing technique.

I'm "guessing" it may be related to upload settings, I'm not sure if partial-file-sharing in LW 5.5 takes into account upload slots & bandwidth set by the user, but either or both of these things may be affecting it. Once I set my upload slots lower, I received this message. When I set my upload bandwidth down very low, the message seemed to come very frequently. And this was via mostly different users for the same incomplete file I was still downloading. I don't usually cut my bandwidth down by much, but I do sometimes cut my upload slots if several large files such as videos are being uploaded. Means they get faster & regular speeds. Otherwise for some reason, if I have many small files being uploaded at same time as several very large ones with many upload requests, my upload bandwidth jumps all about even down to zero at times. Odd. But on this occasion it was purely an experiment where I cut the bandwidth down very low.

My only other thought is, the users programs are requesting parts of the incomplete file I do not yet have. And LW is mistakenly notifying via the incomplete window about this error. In the last example, I had 25-35% of the (video) file completed.



lol just after posting this I noticed a regular shared music concert video file I have with same message in upload window. Then a small file with same message a few minutes later despite pushing my bandwidth back up. My above hypothesis was was perhaps partially correct lol, it might be related to error messages within the program, not enough slots or not enough bandwidth, but the messages being mistakenly reported to the upload window perhaps. The image below was after a couple greedy people tried to select many files to download at once. A & B were about 5 mins apart.



And then another different incomplete file with same message a couple mins apart, whilst a couple people were peaking my upload bandwidth with music & video uploads. Perhaps this post does not say anything. lol Anybody with any ideas?

Edit 3 July 2011:
(Edit August) I had thought problem might be caused by using LW 4's old preferences with no to partial file sharing. But after removing this line from the preferences, still seem to get the error. I suspect the problem is a bug. The Invalid Request seems to occur for both incomplete & shared files. Especially but not only if the person is trying to upload too many files. Seems to happen mostly if they are waiting in queue for a slot.

This is one reason LPE always seems to run best upon a clean install with no previous LW preferences. That includes removing LW Basic or LW Pro preferences.