Lib Dem council leader Mary Rose Gliksten said of her defeat in the Castle Without ward: "I'm obviously terribly disappointed. This is not the Liberal Democrats' night."
New council leader David Burbage said the new administration was to look at abolishing short-term on-street parking charges and would review the yellow lines used on the borough's roads.
He added that the party had exceeded its expectations in Windsor itself.
He said: "We essentially aligned our party with what residents were telling us. We tried to meet what they were asking their local council to do."