A few users have seen this. I think it's a connection issue as I've seen it off and on.
If it was connection problems why does the HTML validate and only the.CSS not work
I think the answer is that it is not a "connection problem"...
The css validation of local files (Document > Validate CSS) consistently has not worked for me in version 14 and - if memory serves me right - in version 12. The error messages have varied somewhat, but most commonly I've experienced the lockup described in this thread and in the prior one that Gunsmoke gave a link to.
I found the answer given to one poster's support topic in the previous thread "...it is caused by Windows very strict security settings..." a bit odd, but I took it at face value and went the route of going straight to the CSS Validation web site for my validations.
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