Assuming you are referring to aluminum storm windows, I've used spray WD-40 on our aluminum storms. It helped, but be sure that nothing else is jamming the window, like paint or having the screens and storms in the same track. I also scrubbed the tracks and channels with a brass wire brush. Obv. leaves and other debris can get into the tracks and keep the windows from sliding and seating properly. If these are NOT storms, I can't help you. Good luck.

I've gotten good results withJig-a-Loo, a silicone lubricant one letter away from a racial epithet.

snort, snort, coffee all over my computer screen.

Paraffin provides an actual lubricant, as opposed to WD40.

Most of the contents of the WD40 can is solvent that evaporates leaving nearly nothing behind for actual lubrication.

You might need to clean any surfaces the rub together with a Scotch-Brite pad.

Aluminum can get pitted and rough enough to cause excessive friction on sliding parts.