2015 cme $0340 error

[comnrailpwr]

I have a dealer with a problem truck that will not accept a csp4 flash. It kicks him off with $0340 every time. Sometimes it almost completes and others it only gets half way then it boots him. He was finally was able to get a stock file back in after 2 attempts. First time it kicked him off with $40. This dealer uses an autocal to flash trucks and I have had him try both autocal and pass through. Have tried "assume lock may be faulty" and with "Fast CAN" off. Nothing seems to work. It is like the ECM is still locked. He unlocked it using an Edge Insight. I have remote into his computer to make sure everything is up to date and it is. We both are running V8.2.5.316. Does anybody have any ideas? I am kind of at a stand still with it and exhausted all my resources I know to do. Much appreciated.

[comnrailpwr]

Problem solved. After we got the stock file in we tried the unlock again. Edge did it's thing and then $0340 again.. Finally after a a third time it actually unlocked and would accept a modified flash. Edge said it successfully unlocked all 3 times so looks like they didn't finish their R&D