Not read i1000 impala ss 2007

[Bigblock03]

hello I have a 2007 impala ss program repeatedly iTunes 1000 and worked well as modifications to take deprogrammed dealer , now I try again d d program it does not capture the parameters and not c q communicates with the car can do

[Bigblock03]

connect the i1000 and light begins to download but ask me if devo pass the key to power and sends the data and the computer does not accept