Check if registry path exists C#

Question

0.00/5 (No votes)

See more:

Hi,

I am trying to understand how Registry works under c#.

All examples that I have found are pretty much same, but I always get null as a result, and I am sure that registry path DOES exists.

For example, I want to check if this registry key (path) exists:

SOFTWARE\Microsoft\Windows\CurrentVersion\WindowsUpdate under HKLM.

I am not looking for strings or values, just if KEY exists or not.

Thank you all for your suggestions.

What I have tried:

var key = Registry.LocalMachine.OpenSubKey(@"SOFTWARE\Microsoft\Windows\CurrentVersion\WindowsUpdate");
if (key == null)
{
// Not exists
}
else
{
// Exists
}

Posted 6-Oct-19 10:09am

AlexaRS

Updated 8-Oct-19 7:55am

Add a Solution

Comments

RickZeeland 6-Oct-19 16:18pm

Are you compiling for 32 or 64 bits ? this can make a difference for which registry is being used.

AlexaRS 6-Oct-19 16:44pm

Hi, it is 32bit

AlexaRS 6-Oct-19 16:58pm

Rick,

it works as x64, but I need it in x86

2 solutions

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

Richard Deeming · Answer 1 · 2019-10-08T07:56:00

Quote:
it works as x64, but I need it in x86

You need to specify the RegistryView that you want to access:

C#

using (var hklm = RegistryKey.OpenBaseKey(RegistryHive.LocalMachine, RegistryView.Registry64))
using (var key = hklm.OpenSubKey(@"SOFTWARE\Microsoft\Windows\CurrentVersion\WindowsUpdate"))
{
    if (key == null)
    {
        // Doesn't exist...
    }
    else
    {
        // Exists...
    }
}

RegistryView Enum (Microsoft.Win32) | Microsoft Docs[^]

phil.o · Answer 2 · 2019-10-06T10:20:00

Solution 1

Accessing anything in the registry which is not in the CURRENT_USER hive requires administrative access.
Try to launch your program as an administrator, and see if that solves your issue.

Posted 6-Oct-19 10:20am

phil.o

Comments

AlexaRS 6-Oct-19 16:27pm

Hi phil.o

it's same behavior, I am local admin, I have turned off UAC, run as admin but it is null.

Meantime, I have noticed that I can reach
SOFTWARE\Microsoft\Windows\CurrentVersion but not SOFTWARE\Microsoft\Windows\CurrentVersion\WindowsUpdate, very strange

On the other hand, I have PS script that works fine and can reach all keys in the node.

phil.o 6-Oct-19 16:32pm

If you check the access rights on said key, you may find out that it has special access rights which prevent you from reading it.
I have checked on Windows 7, mine does not seem to be protected. This could have been changed on more recent versions.

AlexaRS 6-Oct-19 16:35pm

Not a permissions issue. Checked, local admins have full control, and I am able to edit subkeys and values via regedit.

phil.o 6-Oct-19 16:50pm

As Rick suggested, try to compile your program in 64-bits, and see if that changes the result.

AlexaRS 6-Oct-19 16:56pm

yes, it does get subkeys. but I need it in x86.

phil.o 6-Oct-19 17:03pm

Then watch for the key Software\Wow6432Node\Microsoft\Windows\CurrentVersion\WindowsUpdate ; check its permissions.

AlexaRS 6-Oct-19 17:12pm

Thanx, will try that