CK Crash on Load: "File 'Skyrim.esm' is not a valid TES file."

Recently, my empty Skyrim.esm file has started crashing the CK. This is quite out of the blue, and I haven't changed anything since I last (successfully) used the CK to work on Skywind about a week ago. There was a Steam update, so I'm wondering if that's the issue?

Anyway, as soon as I load up the CK with the empty dummy Skyrim.esm in my data folder, I get the warning "MASTERFILE: File 'Skyrim.esm' is not a valid TES file." I click Yes to all, and it opens up the empty CK. I load the plugin I'm working on (.esp that implements Skywind quests), and the next error is "FORMS: TESDataHandler trying to create TESForm for unknown type 'NONE'." I don't remember getting this error last time I worked on Skywind, and sure enough, clicking Yes to all gives me a dialogue asking if I want to truncate Skyrim.esm.

Regardless of whether I click Yes or No, I then get the normal loading process, standard errors and all. Once the CK is finished loading, it crashes.

Like I said, the only change since it was last working for me was that Steam updated. Do I need a new dummy Skyrim.esm? And has this happened to anyone else?

what's your CK version ?

Get a new dummy Skyrim.esm.

Get a new dummy Skyrim.esm. Also, I'm pretty sure if the dummy has to be in Skyrim.esm's normal place that a steam update will overwrite it with the actual Skyrim.esm, which could be your problem.

Grabbed a new dummy, to no

Grabbed a new dummy, to no avail. =/ This is quite baffling.

I'm running CK version 1.9.32.0.

I guess you should check any

I guess you should check any other files you're loading, and if it is failing with just the dummy, reinstall the CK.

I did some quick research,

I did some quick research, and apparently uninstalling the CK would wipe out my Skyrim folder (Thanks a lot, Steam!). I'm going into crunch time so I won't have much time for modding anyway, so I guess I'll just package up and share what I've got so far and sort this whole mess out later... =/

Ever since the surprise Steam update, my entire Skyrim installation seems to be borked. I think I'm looking at a full reinstall... My first for Skyrim! Pretty good, considering how often I had to reinstall Oblivion... =P

Try doing a file validation

Try doing a file validation with Steam. It will replace broken files (probably also the dummy Skyrim.esm AGAIN).

If a reinstall is necessary, you should cutpaste your entire Skyrim data folder to somewhere else, uninstall the CK, put the data folder back in, and tell Steam to validate files (it'll only replace what's missing or broken, and the data folder is the bulk of Skyrim's size), then install the CK.

To do a file validation check: right-click game in games list, click properties, go to Local Files tab, and click "Verify integrity of game cache". It should take only a minute or two to check.

Yep, file validation did the

Yep, file validation did the trick.

Also, you should probably

Also, you should probably disable automatic updating.