How to prevent a user from installing software on a PC?

My system has windows 10 pro installed on it and I want to prevent software installs.

I tried disabling the windows installer using gpedit but it didn't work(I was still able to install softwares without any problem).

I don't want to create more than one user account to solve this.

My answer obviously will not answer your question but I will try to explain why it is useless attempt:

This - "I don't want to create more than one user account to solve this." is the most common error. No one educated administrator would work on computer under administrator's account. It used only for administrative tasks, such as program installations or adjusting settings for the whole computer.

If there only one account, it is means it is administrator's account and if somebody has access to it then he/she can revert all of your restriction attempts. It isn't applied to a real humans only, but it applies to a viruses too. If they runs under administrator account, - it isn't your computer anymore.

You can’t. Even a regular user without any privileges can still install programs to their user account folder.

Well, actually, you can: You need a whitelist of programs that are allowed to run. It must of course not include any user-writable path. This will prevent the user from running anything, including installers. However, maintaining it is a major PITA.

The Windows Installer service is only concerned with .msi packages. Many programs don’t use them, because creating them is rather complex.

You have already received two "You can't" and "it is useless" answers below. But I lean towards more practical solutions than technically correct answers.

But first, this answer applies only if you have Windows 10 Enterprise edition. Microsoft makes good features only available to those who pay more money.

Do the following in the order given:

1. Create one admin account that only you know its password. Create a standard user account that others use. (And maybe yourself too. What stops you after all?) Users with the standard user account cannot install apps into C:\Program Files folder.

2. Using the admin account, enable Applocker to prevent the standard user account from installing apps outside C:\Program files. Excerpt from "Preventing Standard Users from Running Per-user Applications". TechNet. Microsoft:

   To prevent standard users from running per-user applications

   1. To open the Local Security Policy MMC snap-in, click Start, type secpol.msc, and then press ENTER.
   2. In the console tree, double-click Application Control Policies, and then double-click AppLocker.
   3. Right-click Executable Rules, and then click Create Default Rules.

   Three rules are created and listed in the MMC details pane:

   • Allow all users to run files in the default Program Files folder.
   • Allow all users to run files in the Windows folder.
   • Allow members of the built-in Administrators group to run all files.

3. Using the admin account, disable Windows Store. Excerpt from "Disable access to, or Turn off Windows Store in Windows 10/8.1". The Windows Club:

   1. Type gpedit.msc in Run box and hit Enter to open the Local Group Policy Editor
   2. Navigate to the following setting: Computer Configuration → Administartive Templates → Windows Components → Store
   3. Here, in the right pane, you will see the setting Turn off the Store application. Double-click on it to open the Settings box, select Enabled and clicked Apply.