Apache service fails to start (1 reply)

I had to replace my motherboard yesterday and today the Apache service fails to start ?? (Shouldn't be related I know.)

WAMP logo is Orange

I am running:
Win 10 Home 64 bit Version 1607
Apache 2.4.9
C:\WAMP
WAMP Server 2.5


There is an error message in the Windows Event Log:
The wampapache64 service terminated with the following service-specific error:
Incorrect function. Event ID 7024

There are no entries in the Apache error log or Access log (today).

What to check next? I thought of just doing a re-install but reading the forum this isn't totally straightforward.

DG