<p>I got this error when trying to update an image.
It was a cross-thread update, but I used .Invoke(), so that shouldn't be the problem, should it.</p>

(Answering my own question, for others, and for future reference)
I
think
(not yet entirely sure) that this is because InvokeRequired will always return false if the control has not yet been loaded/shown. I have done a workaround which seems to work for the moment, which is to simple reference the handle of the associated control in its creator, like so:
```
```
var x = this.Handle;
```
```
(See
http://ikriv.com:8765/en/prog/info/dotnet/MysteriousHang.html
- down?
cached version
)
(Related question:
Boiler plate code replacement - is there anything bad about this code?
)