Ok, Ill keep this quick.. I have had hardly any crashes at all with Skyrim and the construction kit, used everyday since launch. I have done absolutely nothing to my computer to cause this new issue I am having, and boy what an issue it is. The Creation Kit now fails to startup giving me an instant crash blah blah message Skyrim has stopped working yada yada....I mean I went to bed last night with everything fine and dandy, so this morning when the CK crashed on startup I thought ok lets try again, and again and again........ Now here I am desperate and gone mad with anger because no matter what I do, be it reinstalling the CK, reinstall the whole of Skyrim, cleaned HD, new graphics drivers and pretty much everything you can do to sort a crash of this kind, it still darn well crashed on start. It dosent even give a reason as to the fault. Its extremely annoying that this manifests itself at the worst possible time for me in the middle of a large mod I have been working on everyday scince launch. I am beyond words. The Ck simply will no longer load. For some reason that is impossible to find or locate it has become totaly 100% unuseable overnight, quite literaly.

Now I am a normaly patient fella, but after trying so many things I am now very close to deleting Skyrim from my comp and never playing it again. I have gone from very happy and contented with my work, to being furiously frustrated at the CK and its ridiculous bugs and problems.

Try restating Steam and/or your computer. If not, Steam > Library > View > Tools > Creation Kit > Properties > Local Content > Verify Integrity should replace anything missing. If that doesn't do it, "Delete local content", then reinstall. If that doesn't work, do the local content thing but with Skyrim itself.

Actually it is happening to me as well I tought it depended on my mod but it seems the CK become more instable after the last patch and crashes a lot a lot more ... anyone can confirm this?

Did you create a new Skill ? Because there's an issue like that, it saves fine but then you can't open your .esp anymore as it crashes all the time.