We have red oak hardwood floor. I sanded (24, 36,60,80,100), didn't screen (I know a mistake) and put the two coats of dark walnut. Floor looked beautiful except edges where edger was used and you could see picture frame kind of thing in family room (not too obvious anywhere else for some reason). I tried very hard and after a lot of effort was able to match the stain color and picture frame effect was almost gone. Then I put first coat of Poly (oil based) and it looked good. When I put the 2nd one (after screening grit 220) in some spots poly didn't adhere like there was moisture or something (but that's not possible as weather is dry and I allowed it to dry for 4 days). It's posible it was a bit too thick as for some reason I used like 1/3rd more than the first coat. I used buffer again grit 220 but somehow it didn't become super smooth in some of those spots. I thought that would be OK - big mistake again! I put the 3rd coat and those spots still look rough although poly seems to be adhering now. Is there anything I can do to fix this? If I sand those spots smooth and put the poly again I think it'd never be good right? It'd look repaired from an angle I think. Any suggestions? Thanks

Two coats of stain will take much longer to cure before poly is applied. There is a chance of an adhesion problem because the stain is not completely hard.
You may get success by waiting about a week with good curing conditions before you add the final coat. Try using a matte finish so the surface doesn't reflect showing surface irregularities.

Thanks a lot. I have to admit refinishing hardwood floor has been the toughest of my my DIYs. After 2nd coat of stain I had to leave it for more than a week as I was trying to match the color in family room. Weather was real dry and I kind of believe I gave it enough time to dry. However, my 2nd coat of poly had a little bit too much of poly I guess (1/3rd more than 1st and last coat). Is it possible that didn't dry completely in spots? I gave it about 2 full days with 4 large fans running for a day.

I used Satin finish. I have spent so much of time on this already that I can't do another complete coat (my wife is ready with divorce papers ). Spot repair can be done but if it is going to look like a repair I'd rather live with what I have now and screen it and put another coat sometimes next year when kids are away (oil based poly stinks so much it is almost unbelievable). Any chance I do spot reapir by sanding and putting coat of poly and it wouldn't be too much visible?

Did you buff the floor with steel wool after each coat of stain? This smooths the floor by polishing the grain raise and extra oil off the surface along with help the stain dry when it is borderline dry.
If the finish is good and hard you can add another coat of poly. Some add a little stain in the finish tinting for color matching. Satin will help with surface reflections. It's very hard if not impossible to do touch-up areas that blend.
I go wall to wall if possible with the edge of the board as a stopping point.
With light hitting the floor you will start getting a patina and the floor will look better over time.

Thanks a lot Pete. unfortunately I can't go wall to wall as along the grain that will include dining and living room along with foyer. I will allow it to dry completely for a month or so an then sand and apply poly again. Any tips when I do spot reapir of poly and try to blend it with the rest?

If you did not buff all the residual stain from the surface before you applied the first coat of poly you will have an adhesion problem because you will be dissolving the pigment with the solvent in the poly. It will dry, but not adhere so the next coat of finish will lift the previous coat. Both can just peel off. So when they peal you will be losing some color. You can add color by mixing in universal colors to add where the color is needed as a "primer" before you apply the finish coat to get a uniform sheen. A couple of thin coats of color primer are better than one heavy coat. You are getting a lot of experience with this job. I've seen coats of natural lift where there was a "river" of thicker finish that didn't dry enough before the final coat and was worked on with a razor blade before the previous coat got hard enough to make an attempt at fixing. The finish cures from the top down and if you can not smell it drying it will be cured enough to work on. Thick layers can take almost a month depending on the brand.

Thanks Pete. I have decided not to do anything now and work on it in summer. I do realize it was all because coats didn't dry completely. I plan to screen the finish, remove all imperfections as best as I can and then add a coat of poly.