Crash when I go to Layout-Header Footer

Every time I go to Layout-Header footer I get a crash

Internal Server Error

The server encountered an internal error or misconfiguration and was unable to complete your request.
Sometimes I can get it to load (very random)

Anyone else experiencing this?

it was doing it on SC 9 and I was hoping SC10 would resolve it .
I have checked the logs I can find but no clues.