EDIT: SOLVED it was nod32 just add exeption for java binaries
Hi,
When the connection is lost the URL is disabled!!!
I have nod32 AV and the HTTP and URL things are all disabled,
max conn is 1
working with free Megaupload.
Win XP SP3. java version "1.6.0_17"
JD
Log file:

------------------------  Thread: 32  -----------------------
32 24/02/10 16:07:41 - FINER [java_downloader] -> Start Chunk 0 : 23492962 - -1
32 24/02/10 16:07:41 - FINER [java_downloader] -> Übernehme Verbindung bei 23492962
32 24/02/10 16:07:41 - FINER [java_downloader] -> ServerType: RETURN Rangeend-1
EXCEPTION   32 24/02/10 16:08:11 - SEVERE [java_downloader] -> SEVERE Exception occurred
java.net.SocketException: Connection reset
	at java.net.SocketInputStream.read(Unknown Source)
	at java.io.BufferedInputStream.read1(Unknown Source)
	at java.io.BufferedInputStream.read(Unknown Source)
	at sun.net.www.MeteredStream.read(Unknown Source)
	at java.io.FilterInputStream.read(Unknown Source)
	at sun.net.www.protocol.http.HttpURLConnection$HttpInputStream.read(Unknown Source)
	at java.nio.channels.Channels$ReadableByteChannelImpl.read(Unknown Source)
	at jd.plugins.download.DownloadInterface$Chunk.download(Unknown Source)
	at jd.plugins.download.DownloadInterface$Chunk.run0(Unknown Source)
	at jd.plugins.download.DownloadInterface$Chunk.run(Unknown Source)
32 24/02/10 16:08:11 - SEVERE [java_downloader] -> error occurred while writing to file. Connection reset
32 24/02/10 16:08:11 - SEVERE [java_downloader] -> Error occured: ERROR_LOCAL_IO
32 24/02/10 16:08:11 - SEVERE [java_downloader] -> A critical Downloaderror occured. Terminate...
32 24/02/10 16:08:11 - SEVERE [java_downloader] -> ABBORTED BY USER
32 24/02/10 16:08:11 - FINER [java_downloader] -> Chunk finished 0 164786 bytes

------------------------  Thread: 30  -----------------------
30 24/02/10 16:08:11 - FINER [java_downloader] -> onCHunksReady
30 24/02/10 16:08:11 - INFO [java_downloader] -> Close connections if the are not closed yet
30 24/02/10 16:08:11 - INFO [java_downloader] -> Closed connection before closing file
30 24/02/10 16:08:11 - INFO [java_downloader] -> Close File. Let AV programs run
30 24/02/10 16:08:11 - SEVERE [java_downloader] -> DOWNLOAD INCOMPLETE DUE TO FILESIZECHECK
30 24/02/10 16:08:11 - SEVERE [java_downloader] -> Error occured: ERROR_DOWNLOAD_INCOMPLETE
30 24/02/10 16:08:11 - SEVERE [java_downloader] -> DOWNLOAD INCOMPLETE DUE TO FILESIZECHECK
30 24/02/10 16:08:11 - SEVERE [java_downloader] -> Error occured: ERROR_DOWNLOAD_INCOMPLETE
30 24/02/10 16:08:11 - WARNING [java_downloader] -> 
Error occured- latest: ERROR_LOCAL_IO
00100000001001000000000000000001 <Statuscode
00000000000000000000000000000001 |TODO
00000000000001000000000000000000 |PLUGIN_IN_PROGRESS
00000000001000000000000000000000 |ERROR_LOCAL_IO
00100000000000000000000000000000 |PLUGIN_ACTIVE
StatusText: Idle
ErrorMessage: No permissions to write to hard disk

no, the problem isn't solved...
It was OK the first time then the downloads are disabled when the connection is lost showing the same error message!!
I removed nod32.
Now I don't have an AV nor any other security software (firewall...), I also disabled windows firewall.
I'm using JD 0.9.579

If you are running a torrent client (that's using a lot of connections), please stop it.

Re-install JRE (java). Your version is OK.

If you have an unstable internet connection, then contact your ISP.