[williamx]

I have read on this and other forums about the problems, cleaners have with spotting?.

From what I have read its seems to happen for no apparent reason, which can't be right.

I think that if we all report what conditions we were in when our windows spotted, we might find one or more common causes.

For instance are the houses that you clean on a main road with a lot of traffic ( traffic fumes) or in a cul de sac?