upgrading vista to windows 7 installation problem

while upgrading my vaio to windows 7, the installation made it to the final step and at the final restart it said that it the installation was unsucessful and to restart the installation except that i cant because the computer cant boot up.. it only restart and goes to the same error window over and over again.. what should I do?

Is this a retail disc? Are you doing a clean install or upgrade?

i got the disc from the sony windows 7 upgrade program.. my sony vaio was eligible for the upgrade not sure if its retail.. its an upgrade for sure

Did you read the instructions? I think the sony website listed you needed a factory fresh pc before an upgrade. Try to reboot with the disc in the drive, then choose custom, format everything and then install 7 in a new partition.