I have an old Buffalo NAS (network attached storage) drive. It was bought years ago, but it has 1GB of disk space and this makes it useful as a backup device for other computers on the network.
It is switched on only once a week to make a backup (I know I should backup more often, but most files are in the cloud and not on the computer anyway), and the last time I turned it on, the computer could not find it. It did not appear in Explorer windows and the backup software could not access it. It was definitely running though.
It is a good idea to check the firewall in a situation like this where a networked device like a NAS drive or a wireless printer cannot be accessed. Windows Firewall was being used, so after opening it in the Control Panel, it was switched off for both public and private networks. It made no difference to the problem though.
The next step was to check that it was actually on the network. The router keeps track of all network devices and you can log on to the router’s admin interface by entering the IP address into a web browser. Mine is 192.168.1.254 which is typical and many routers are 192.168.1.x.
There are many custom router admin interfaces and navigating them is just like navigating a website. Find the right page and you can view the IP addresses of all the devices that are connected to it. The NAS drive, with the product code LS-CHL-V2AB0 was there alright.
Knowing the IP address of the device, it can then be pinged. The ping command sends test data to a device or web server, which then returns it. This tells you several things and one is whether the device or website is working. Non-functioning devices and websites do not return the data, but when they are working OK they do. The time taken for the data to get there and back is also measured, so you can see whether a device or website is operating normally or very slowly for some reason.
Press Windows+R and enter cmd to open a command prompt window. Then enter ping 192.168.1.85 or whatever the IP address is for the NAS, wireless printer, or other device.
The odd thing about this is that once the NAS drive had been pinged, it magically appeared in Explorer and could be accessed normally. If you are in a similar situation and cannot access a networked device, it might be worth trying ping.
If you cannot access the router to discover the IP address of a NAS drive, wireless printer or other device, you can use a utility like Wireless Network Watcher. It scans the network for devices and computers and lists everything it finds.