Server side includes not working?

[#1]

Now that the server has been restarted, I see that my pages are not taking any notice of the server-side include directives in my .shtml files, e.g.
<!--#include virtual="header.php" -->
and consequently the pages are not displaying correctly.  This all worked fine last week.
What do I need to do to get it working again?

[#2]

Not something you can override yourself. It would need to be set in config. Plusnet may pick up on this.
Gabe

[#3]

All my sites are knackered until this is fixed.

[#4]

Edited.

[#5]

I've raised a case internally to have somebody look at Server Side Includes (ref: 300232).
Edit: should now be fixed, can you try again?

[#6]

Yes - seems to be OK now.  Thanks

[#7]

Mine are working now - thankyou