Why is a subst drive usable from a command prompt but not Windows 7 explorer

Question

I have a registry key under [HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run] The value of the key is

"c:\windows\system32\cmd.exe" /c subst t: e:\MyFolder

More often than not when I boot the computer the subst command appears to only half work. If I open a command prompt I can use t: fine. However if I look in windows explorer T: is not there and if I type it into the address bar I get an error message saying "Windows can't find 't:'. Check the spelling and try again."

This is on Windows 7 Enterprise 64 bit.

Any ideas?

Solution 1

This command creates a persistent Z: subst of C:\DirectoryName

reg add "HKLM\SYSTEM\CurrentControlSet\Control\Session Manager\DOS Devices" /v Z: /t REG_SZ /d "\??\C:\DirectoryName" /f

Solution 2

This probably happens because the run command runs elevated (as administrator). If you run the subst command not elevated you will see it in Windows Explorer. You can test this running the subst on an elevated command prompt.

Solution 3

Use PSubst 3 utility. It is a DOS batch file that maps a drive permanently. Works in every windows version after XP.

Github Repository

Download latest version Direct link

Solution 4

https://github.com/ildar-shaimordanov/psubst

This is original repository of the psubst tool enabling SUBSTed drives be persistent between rebooting.

View more solutions

Comments

[Xantec]

i've never used subst myself, but this is what Wikipedia has to say on setting up a persistent mapping. hope it helps

[Pacerier]

@Dan, Here: How to make SUBST mapping persistent across reboots? ..

[LawrenceC]

There are so many layers of APIs and wrapper .DLLs in Windows that it's actually surprising when you make a change that is indeed visible everywhere. The command first appeared under DOS so that's it's "expected" environment.

[Jim Fell]

I tried this, but it still didn't take.

[Victor Zakharov]

+1. Still works in Windows Server 2012. Needs a restart.

[Mickey Perlstein]

Did not believe this would work, but you were right! it worked i mapped my dropbox to Z: on the fly. well done

[Starnuto di topo]

Does not work on Windows 10

[Eryk Sun]

@Starnutoditopo, it works fine in Windows 10, assuming the cmd shell isn't elevated.

[Julius Bullinger]

It does not work on my Windows 10 machine with version 1607/build 14393. Can anyone confirm?

[vic]

Windows 2019 Server, still works, so Win10 should work, too. But because the setting is in HKLM, a reboot is required, a mere logoff is not enough.