image crop area preview requires mouse interaction on IIS

Hi,

This happens every time I setup a WP site + every time I forget to make a note of the fix!

Fresh install of WP through IIS Web Platform Installer. All working fine, but when I try to set an image through the Media Library, I get the above error when I get to the crop image stage.

I’ve got IUSR and IIS_IUSRS permission set to full permissions. Weird thing was – I cycled the permissions (unchecked, then checked again) which allowed me to crop an image that I’d uploaded already. However, when I uploaded a new image and tried to crop, got the same error… 🙁

Done some googling – can’t find a bug shoot on this one. I’m sad that WP doesn’t play nicely with IIS right out of the box!

Any help much appreciated