I am in the middle of proofing a job that uses multiple transparencies and blending modes... the proofs looked good (or so I thought), I sent them out for approval (PDFs). Nope, the customer has come back saying the color in the proofs look different than the original files the designer sent. Hmmm....I check the files and they look the same as what the designer sent. What the?.... A phone call to the customer reveals that she is viewing the original (designer's) files without the overprint preview on and comparing them to my proofs (which have overprinting embedded in the file). Really?! Turns out, the designer never showed the customer proofs with the overprint preview on and now they are asking me to try to match color to what the files looks like without the overprint preview on! This is beyond annoying.... I adjusted the files as close as I could (literally by taking the blending off and adjusting transparencies and changing the PMS colors used...). They still don't match perfect and shes very picky. Would you guys tell the customer to go back to the designer or try to make magic for hours adjusting colors and transparencies?