Hi,

I've got an old Dell Latitude E6400 which is running Windows 10 Pro now. I'm very happy with it and don't use it very often, only once or twice a week because it has a Photo editor software which I can't install/use on other machines unless I pay for it. It always sit on an E-port dock, connecting to an external monitor.

This morning, when power on the machine, a message was saying the RTC baterry is not there but machine still boot after hitting F5.

I turned it off and went out. After lunch I tried to turn it on to continue my work but it won't boot and it said it can't find the boot device. I re seated the SSD (yes, I swapped 3 or 4 years ago) and rebooted, now it said it can't see the keyboard and still can't boot.

I think all could be related to the RTC (CMOS) battery. Please let me know what is other possibilities which caused the problem.

Regards.