Just be careful with international roaming charges.

https://www.theguardian.com/us-news/2024/apr/18/143000-t-mobile-bill

Hi Jeff. The error message "Err" has cleared up. Since you have been at the Nikon repair center in Signal Hill, could you let me know if I can just go there and talk to a tech, if the "Err" issue was to reappear?

I can only guess it is. I prefer using isopropyl alcohol (100% alcohol) than rubbing alcohol which is diluted with a small amount of water.

Thanks for reminding me about the existence of the locking tab for the f-stop ring. It was locked on my lens, but I had forgotten about this lock. Now I remember having unlocked it one time when I was using the lens in conjunction with my Nikon PB-6 Bellows, and needed to set the diaphragm manually.

As I was telling in my original posting, while taking pictures the camera suddenly froze. When I realized none of control buttons were working, I tried to shut it down but to my surprise I couldn't even do that.
I then pull out the battery, and later re-inserted it, the Err message was still being displayed. So I removed the lens, the battery, the two cards, and the remote electronic trigger but again after re-inserting the battery the Err message was there.
It was late in the evening so I put the camera aside and decided to check it again the next day. In the meantime I posted on this site for help and did some searches on Google. As someone suggested I decided to clean the electrical contacts on the body and the lens. After mounting the lens and powering the camera, the Err message was gone.
So far after taking a bunch of pictures, the issue seems to be gone. However, I'm not 100% sure if cleaning the contact was what fixed the problem.

@Russraman. Beautiful picture of you and your dad. By looking at you as a baby, we should be very close in age. I was born in March 1949. I have tried to use the auto-focus when digitizing negatives, but always had better results doing it in manual focus.
I'm impressed that you did process 10,000 slides, since the holder can only hold two slides, that's a monumental task.

Thanks BurghByrd. Yes I have done all of that except using a pencil eraser to clean the contacts. Someone warned me not to use one. The pencil eraser will create small rubber particles that will land on the mirror and/or on the back of the lens. Instead I used a Zeiss microfiber cloth towel wetted with isopropyl alcohol to rub the contacts.

Thanks Russraman. Yes I always check that the AF Micro 60mm aperture ring is set at 32 prior mounting it onto the body.
BTW, my D850 is now working fine. It could have been a bad electrical contact between the body and the lens.
See my other replies.

[quote=jlg1000]If this is correct (waiting for your confirmation) it would be another example of what I call "Malicious Offuscated Error Threat"

The error "Err" message on the top LCD magically disappeared after having the camera body resting overnight with the battery, lens, and memory cards removed. Following some recommandations I also cleaned the electrical contacts on the body and lens.
I agree that Nikon could be a little bit more explicit with their error messages. I understand that the space available on the display is constrained but adding a number after "Err" like for example "Err3" could be useful. It would only take a simple Google search to find what's has gone wrong.

I found the problem by doing a Google search. It seems most Err issues are caused by bad contact between the lens gold contacts and the camera contacts.

https://www.google.com/search?q=Getting+an+Err+message+on+my+Nikon+camera&oq=Getting+an+Err+message+on+my+Nikon+camera&aqs=chrome..69i57.14489j0j15&sourceid=chrome&ie=UTF-8#kpvalbx=_D6ynY8ugKriYkPIPjLCHwAU_37

Yes I did. However, the Err message persisted.

Will do. Thank you for letting me know.

Yes I did.

They will only give you a quote after they receive the camera. I won't be able to send it before next Tuesday

While digitizing old 35mm strips of B&W negative film using the ES-2 Film Digitizing Adapter, my D850 suddenly froze. I couldn’t even turn it off. A warning message was flashing “Err” on the top LCD display. I researched this issue on the Nikon site, but besides trying to swap batteries there were no other ways to fix the problem, except to send it for repair. Nikon describes this error message as a hardware issue that cannot be fixed by resetting the camera, which I couldn’t even try because nothing was working anymore.

I’m interested to hear from members who may have experienced this hardware failure and how much Nikon charged them for the repair, assuming their camera was out of warranty.

Below is the configuration I was using:

2018 Nikon D850 with ~ 5000 shutter actuations
ES-2 Film Digitizing adapter
AF Micro NIKKOR 60mm f: 2.8 D (lens set on Manual focus)
D850 body set to Manual focus
Exposure Mode set to Manual
Focusing from “Live view” with MC (monochrome) selected
Remote shutter actuation via the Nikon WR-R10 + WR-T10
Prior to starting taking pictures I performed a Clean Image Sensor.

At least one good news, I just found out that Nikon still has a repair center located in Signal Hill, Southern California, which is ~ 45 miles north of where I live. I had read somewhere that Nikon had closed all their repair centers in the US except for one located in New York State, well that was wrong.