Cleaning tree sap past its sell-by date outside window ? I have just taken over a pane cleaning round and am finding...

I have just taken over a pane cleaning round and am finding a lot of windows stained beside what appears to be tree sap , usual cleaning methods will not remove it , any suggestions ?
I am looking for a grandfather clause" my...
Turpentine.

Where do I progress to bring a replacement...
Try Spray 9 degraser and then dry-clean with water to not will a film. You can by it in hardware stores, and Home Depot.
How to money brushes surrounded by a henry...
Maybe you own to upgrade your cleaning methods (by adding soap to the water, maybe?)
Shower Pan removal and Re-Install near topical.?
Answers:    Try spraying with WD-40 or alcohol.