Un supported service tag means the unit did not have any My dell downloads and or its a pirated tag that was flagged to many laptops. There is no fix for this. 
hi I bought a dell latitude e6430 on eBay and it did not have a hard drive and I put a new hard drive and installed windows 7 but I need to know what software came installed on it factory I tried my dell downloads and it says unsupported service tag. PLEASE HELP!! 
Dell latitude e6430 software