Salli3 Ma3 denied me even when trying multiple/different co-signers?

To make things worse, the university first told me I was approved & accepted for the Parent (PLUS) Loan for total cost of tuition.......then I got the denial letter in the mail!!! So this was my last option for the smart option they offer, but I just keep getting denied I have no credit history, my family members either have decent or very bad credit history so it seems like I have no hope here....even w/t the additional $4,000 from the denial of the plus loan i got in stafford loans, I am still about $10,000 short for tuition to go to this school which is my only option