V10 /umbraco suddenly blank

I’ve been working on a site for months, regular updates with no issues at all. Then suddenly today when I make an update the /umbraco directory is just a blank page.

No errors or anything. I’ve not made any changes that I know of to cause this and it runs fine on local machine. So I assume a configuration issues.

Is anyone point me in the right direction?

Umbraco 10.3.2 running on IIS 6.12 Win 2012 R2 (soon to be upgraded)


This is a companion discussion topic for the original entry at https://our.umbraco.com/forum/110645-v10-umbraco-suddenly-blank