Rust stains and more than likely they are not coming off the vinyl. I have had similar stains that I was never able to remove, even slightly.

They are rust stains, and most likely coming from that window. They cover the siding under that window from one side to the other. I would have a window person come and check that out. Even if you could clean it, off, it will come right back, because something in there is rusting.

The breakmetal covering and/or vinyl siding over your window is leaking water underneath the metal and is leaching out rust or whatever it can. It's also rotting out the wood below if left that way. You need to find someone in the siding business to find out the problem.

So these stains are all over the house. Not just under my windows. It just happen the photo I took was of the ones under the window. But there are others not near windows or doors

I just read your other post about the cracking all over the house now. Get your roof inspected right away, this has to be water intrusion.

Rust then from the nails holding the sheathing, framing, windows, trim, all the above. You have water infiltration issues. Get a contractor to look at your roof for starters. Did you have a home inspection? Do you have pictures of the roof?

Maybe it's not water intrusion. The picture of the window has the stain in the "shadow" of the extended window on both sides. Are the stains worse under the eaves and at similar places where rain can't easily wash it off?

Do you have a sprinkler system? if so, see if it sprays on the house. Sprinkler water spraying on the house can cause these types of stains.

Please post more photos of the exterior stains and interior paint damage. Let's have some shots from farther back, too, please.

So these stains are all over the house. Not just under my windows. It just happen the photo I took was of the ones under the window.

Yes, more pictures of the whole house.

1940 house. Is the original siding intact underneath the vinyl? If so, what is the original siding made of--redwood or cedar, perhaps? Longshot that the stains could be tannin bleed but does look more like rust stains. I have removed rust spots from vinyl siding w/ Bar Keeper's Friend--spots where a metal tool or something had been leaned up against the house.

Thank you all for your insight! Here are some more photos. I am not sure what the original siding is. I do know that that roof was just redone within 10 years. I also know that 2 of my neighbors have the same problem.

I would try, cleaning it, at least in one area, and see if it cleans it up. I also do not see gutters, do you not have them?

I was wondering if you've tried cleaning it with anything yet. I just use a bucket of soapy water and a scrubby sponge when I'm cleaning vinyl siding.

^^What PartyMusic said except I also use an old dust mop to scrub the bulk of the siding. You can also use a hose end sprayer to wet the siding down with soapy water or a commercial siding cleaner. Presser washer if you have one.

I can't say for sure whether that's just dirt, or something more insidious. I agree that combined with the odd patterns here, your interior paint problems worry me.

If it's just dirt, I've tried pressure washing and I still find that the quickest and most thorough way to clean vinyl siding is with ordinary dish soap in warm water, and a scrub brush. To minimize the need for ladders, you can get scrub brushes that can be threaded onto extension poles, both at hardware stores. Telescoping extension poles meant for paint rollers fit these brushes. If necessary you can even lash a couple of poles together for a good long reach. Dampen the siding with a spray from the hose, scrub an area, rinse with hose, done. Don't go overboard with the hose pressure.

I have tried soap and water and have a pressure washer that tried multiple times. I do not have gutters on the house.

Are you in an area, where you should have gutters?

The second picture looks like a rust stain. Try Bar Keeper's Friend & elbow grease.

Rent or buy a borescope, view the insides of your walls. I think you have water problems.

Did you ever figure this out? My siding looks exactly the same, with my house being a similar age and style. thanks thanks!

Easy fix. Go to lowes and buy some rust aid. Its hydrochloric acid. Put it in a pump up sprayer and watch it disappear. Thank me later.