I added flooble script in the <head> section of the theme. Then I deleted it as it didn't generated expandable menu. I clicked on reset presuming that the former settings (default) will come up. However, the site wasn't seen online.
I changed to Twelve Eleven theme and all was okay.
Flavicon slips into default repeatedly.
Is W3TC the culprit?
I am now again reinstalling wordpress along with the theme.
Hope it succeeds.
Montezuma does not appear to be robust.
Any mistakes I did?