Option Name Manager in my 1.3.8 Admin stopped working

[PUREchocolatetruffle]

I'm running Zen Cart 1.3.8a and have tried to make the add on attribute_popup_large_images work and suddenly my Option Name Manager in Admin has stopped working.
When I click on the menu "Option Name Manager" I get the white screen and a "Oops! This page appears broken"

Anything else in my store and admin menu works perfect.

How can I get Option Name Manager up and running again ?

Any advice would be very welcome. Many thanks.

Kim
PURE chocolate truffles

[PUREchocolatetruffle]

Sorted, somehow I must have managed to delete the options_name_manager.php. Although I really can't see how.

Sorry for having waisted your time.

Kim