"Klettke" wrote in message
news:Yh7ri.51955$Io4.32815@edtnps89...
I have some older Plexi aircraft windows where the paper protection has
been on for a very long time. Some of the paper has shrunk and cracked into
strips, but is stuck well onto the plexi.
I tried water to soften it, but to no avail.
Any suggestions?

This might be a job for WD-40, try it on a corner to be sure it doesn't harm
the plexiglass.