>You may not THINK the validation rules are violated, but they ARE. Figure out which one and fix it.
>
Weird, but once I commented the StringLength for extension, the IsValid now comes true. Why would StringLength(5) cause a problem?

Anyway, at least it's a next step.

And now hitting the next error trying to update data:

Now it seems to be 'String or Binary data will be truncated message'. Strange again as I only put few characters in the Address field and didn't change anything else. Luckily I think I'll be able to figure out this problem using profiler.