Kraken and Coinbase both have degraded services as a result of so much traffic using their services. This has been going on since late December. They both say they are working to upgrade their respective services and that should be accomplished shortly but who knows in reality how long it's going to be? It's a frustrating situation.
The kraken was trying to do a major system upgrade while the OP was trying to withdraw. The upgrade didn't work and was postponed for a few more days.
Perhaps if the OP cancels his withdrawal and tries to make another it will work the second time. Bearing in mind that by all accounts every button click on the kraken can take hours to get processed.
https://blog.kraken.com/post/1436/system-upgrade-on-saturday-january-6/Note: In the process of performing final checks ahead of rollout, we discovered a problem in one of the system components. We have been unable to resolve the issue in the last 24 hours and expect to make another attempt after the issue has been resolved, in the next few days. We will make another announcement when we are ready.