LG VX-8100

I had a similar problem, and resolved it by buying another cable! The first one I bought was from cellphone shop, it claimed to work for the 8100, it did work for my son's 5200, not my 8100. Bitpim did not detect that phone. They were nice enough about sending a 2nd one to try and taking it back for credit or exchange. I tried another I ordered from ebay, seller was summit image, and it worked like a charm immediately with bitpim. Better to cut your losses and try again! 🙄 Luck!