ip not valid

hi
why sometimes when jdownloader automatically reconnects(wifi) windows 7 x64 show me limited connection ,and when i diagnose it tell ip address not valid.
every time it happens i have to restart modem maualy.
will somebody tell me how to resolve. Reconnection code is devolped by reconnection wizard. MODEM TP LINK W8910G

[drbits]

TP-Link is probably using a short-term pass-code that is in the script code, not the headers.

Please use a web search engine with (site:jdownloader.org upnp) to see if any of the UPNP scripts will work for you.
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