I did a FULL shutdown of my Dell XPS-8900 PC (the one I've been using for all of my tests) and this morning "Devices & Printers" (D&P) took 2min, 10sec to open. WTF! I had it down to 13sec before.
I had my inkjet and laser printers powered off. So I did a full shutdown, powered on both on printers and booted Win10. This time D&P took 1min, 40sec. *#$!
After digging into SETTINGS > DEVICES, in the "Connected Devices" tab, I found a "Bluetooth Settings" link. I opened it and Bluetooth was set to "ON". I set it to "OFF".
Did a full shutdown and then after booting up, D&P took 12sec ! ... Just to be sure, I did a full shutdown again and after booting up, D&P still took 12sec.
So Bluetooth being turned on in SETTINGS > DEVICES was the culprit for my D&P 1min+ delays. Thinking back, I had previously disabled both Bluetooth settings in "Services" and it didn't make any difference (so I returned both settings back to manual), but I had my old HP printer driver still installed at that time. As previously posted in this thread, removing the old HP printer driver brought my D&P opening time down to 13sec. Why the Bluetooth in SETTINGS > DEVICES being on at that time still allowed the 13sec opening time for D&P, I haven't a clue.
Anyway, for folks who are having the 1min+ D&P delay, maybe try turning off Bluetooth in SETTINGS > DEVICES and see if the delay is reduced to 12sec or so.
I just plugged in my USB Bluetooth adapter and speed at which Devices and Printers opened is just the same, instant ! So, it might not be BT itself but something it pairs or tries to pair with.
Turned BT on my Lumia phone, it paired right away with PC and again Devices and Printers opened is just the same, instant ! Same thing even after restarting PC.
So, if BT is to blame for it, it must be a device that (unsuccessfully) it tries to connect with.
I have Bluetooth disabled in UEFI/BIOS. So it does not even show up in Devices.
I have not timed my delay in quite a while. In the beginning it was about 20 sec, much longer compared to Windows 7 (near instant) so to me that was a problem.... period.
My delay is about 15 to 18 seconds today. Still a step down (a few steps down) in performance from W7.
Thanks for your responses.
Last night I did a hibernate instead of a shutdown. This morning I booted up and Devices & Printers took 2min to display. Bluetooth in Devices was still turned off. Devices & Printers is just unusable for my particular configuration.
So everyone, please disregard my previous post about turning off Bluetooth in SETTINGS > DEVICES as being a possible fix.
I give up. MS & screwy Windows 10 wins.
Takes about 3 secs on my laptop.
For me, the problem is fixed when I uninstall the Intel Display Audio driver from Device Manager. Trouble is, it reinstalls after a reboot.
Same for me, discovered when I had problems connecting BT headphones, went to check under devices & printers & it took much longer than usual to open. I solved the headphone connecting problem (Bluetooth was disabled) but don't know where to start with this.