I have checked all four ways (the fifth way is to do something drastic with the Windows installation). Everything in services, the Registry, etc. were already set at the correct values. I had already done all these things before I originally posted here, but had not done the repair update. Now, after the update, everything is still correct and I still get the error, so I'm back at square one.
Let's try looking at it from your original symptom - no drive letter assigned to USB drives.
Please work thru:
Windows Doesn't Assign Drive Letter to External and USB Flash Drives | Windows OS Hub
Similar:
https://answers.microsoft.com/en-us/...7-37eb2da48a47
Some have found this resolves it:
fromThis is an issue I encountered with Windows 10 as well. Fortunately, there's an easy solution that does not require any third-party downloads or registry modification.
1) Open Command Prompt as Administrator (search for Command Prompt in the Start Menu, right click, Run as Administrator)
2) Type 'diskpart' and hit Enter.
3) Once in the DISKPART command prompt (it takes several seconds to load) type 'automount enable' and hit Enter.
That should re-enable automatically mounting new volumes, fixing the issue.
Windows 10 does not assign letter to USB drive | Tom's Hardware Forum
We are making progress! VDS was already enabled. I used 'diskpart' and the USBs are now automounting with drive letters. Thank you!
The pesky RPC server issue, though, persists. When I'm in Disk Management if I try to 'Refresh' the disks or 'Rescan Disks' the 'RPC server unavailable' or 'Remote call failed' errors pops up. Right now it's only on Disk Management but I'm afraid it might impact other processes down the line. What do you think?
Try a clean boot, then retry Disk Management.
Likewise in Safe Mode
Worth doing some background reading.. might prompt an idea.
Troubleshooting 'RPC server is unavailable' error in WIndows
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