I experienced this same issue after replacing the battery. Your post is making me feel less crazy. I will follow your steps. Is your camera still working after a month?
It worked fine for about 3 weeks. Now it is more intermittent - I think, when it is getting warmer it doesn't work, but if you turn it off and on a few minutes later it works. (It's my wife's and I think she's being less careful ;-).) I'm going to open it up again to see if I can pinpoint the flakey connection. I'm wondering, other than the speaker, whether the inner back shield is really needed. (I've made it easier to open, for now, by only using a couple of strips of double sided tape instead of the full 'waterproof' seal.)
I removed my SD card and factory reset the phone without installing a backup and therefore without installing any non-native apps. My camera still doesn't work. If anyone has a solution it would be greatly appreciated. Thank you.
Sorry you're experiencing this issue. Unfortunately I haven't been able to find a consistent solution. It's still intermittent. Coincidentally, I took the phone apart again the other day, disconnected the battery for about 20 minutes and it worked after reconnecting (before putting the back on). I then (looking in a mirror), started searching for a connection issue and nothing I touched or pressed on would make the camera stop working. I restarted the phone and it didn't work. I disconnected the battery again for 1/2 hour and put the phone all back together before turning it on. The camera worked the first time. But not the second time. Clearing cache, etc. does not work.
For what it's worth - my wife is now going to get an IPhone. it's really unthinkable that with so many people having this problem over so many versions of the phone, that Samsung is not acknowledging it and/or putting out a patch. I still do think it's a combination of hardware and software, but it should be solvable. If it's their way to get us to "upgrade", let me tell them - why would I upgrade a phone from a company that does not acknowledge it's defects.
Sorry to go off on a rant - good luck with your phone.
I had the same problem. The camera stopped working after a system update in Feb 2020. I tried all the methods. Sometimes the camera would work for 5 minutes and then stopped working. I am really disappointed by Samsung.
Yes, I also think it's related to an update. I tried to find out, back earlier in the year, if it's possible to roll back from an update and got nowhere. As best as I can guess, there's something that gets in the memory that inhibits the camera app and only disconnecting the battery clears that fragment in the memory.
What's worse (though maybe not unexpected) is the so-called Samsung employees on this forum who give useless responses and do not acknowledge how widespread the problem it. We probably should have quarantened our phones from Samsung earlier in the year.