Most exchanges have been freezing due to the strain all their new users are putting on their systems. The kraken had to do a massive upgrade to its severs after months of problems. Straining those exchanges to that extent would be much harder to fake. Most Bitcoin exchanges won't let you trade until you supply KYC documents.
it has been 6 weeks now you can not even get the process started at Bittrex
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Dear new users:
We have received an enormous number of new account registrations over the past few weeks. We are excited to have so many new users who want to join the Bittrex community. Unfortunately, we have to make a few upgrades to our support and backend systems to handle the increased traffic and load. As such, we have halted new user registrations for the time being. If you already have an account on Bittrex, you will not be affected by this change. Please continue to the log in as you normally do.
To our new users, we will keep you posted on when we open up registration. We apologize for the inconvenience!
The Bittrex Team