What are Potentially Unwanted Programs (PUPs)?

Potentially Unwanted Programs (PUPs) are apps that install without your clear permission and usually add little value. They’re often bundled with other software, so it’s easy to miss the tiny checkbox labeled “install TotallyLegitSoftware” when clicking Next during setup.

Below, you’ll find the full definition and the main types of PUPs, along with real-world examples and potential risks. We’ll also cover how to spot and prevent them, plus nine practical steps to remove them and any leftover system changes.

What are Potentially Unwanted Programs (PUPs)?

Potentially Unwanted Programs (PUPs) or Potentially Unwanted Applications (PUAs) are apps that often install alongside software you actually want. They can slow down your system, display extra ads, or monitor your activity. While they’re usually not outright malware, they can still be annoying and intrusive.

PUPs can get onto your system through bundled installers, misleading prompts, or by appearing in deceptive ads and promotional tabs on mobile storefronts. On the surface, they appear to offer features such as system and registry optimization, disk cleanup, and more.

However, they often prove useless or even harmful. Most of them serve as data-collection tools or as ads for a premium edition that supposedly unlocks all the actually useful features.

What are Potentially Unwanted Modifications (PUMs)?

Potentially Unwanted Modifications (PUMs) are changes made to your registry, file associations, and other system settings without your clear consent. They may persist even after removing the PUP or malware that caused them.

PUPs vs PUMs: What’s the difference?

PUPs are the programs themselves, while PUMs are the changes those programs make to your system. You can remove a PUP, but the modifications it left behind may still affect your computer unless you fix them separately.

Types of Potentially Unwanted Programs

PUPs come in many forms, ranging from minor annoyances and bloatware to software that slows your system or behaves dangerously close to spyware. More details below:

• Adware: Shows ads or pop-ups that usually interrupt browsing. Some may track your behavior to show more targeted ads, while others may resort to malvertising to further infect your device.
• Trackware: Collects system information and monitors user activity, often sold to advertisers, data brokers, and others. Unlike spyware, it doesn’t actively hide itself or collect passwords, payment information, or other sensitive data.
• Browser hijackers: Change your homepage, search engine, or tabs without permission. They redirect you to unwanted sites (usually affiliate pages) and can make browsing confusing or unsafe.
• Unwanted extensions: Add-ons that modify your browser settings, inject ads, or spy on you. Even seemingly harmless extensions can add clutter and affect browsing performance.
• Hacking tools: Programs that bypass security measures or exploit vulnerabilities, sometimes installed by mistake alongside other software.
• System optimizers: Claim to speed up your device but usually make unnecessary changes or advertise other PUPs, and may even break functionality in some cases (the typical “registry cleaners”).
• Driver updaters: Promise to update drivers automatically, but may install incorrect versions, add PUPs, or nag you to buy the full program.
• Fake VPNs and antiviruses: Most in this category are malware designed to steal your sensitive data. However, some are simply PUPs looking to make easy money by tracking or pushing a bogus premium edition with no security benefits.
• Dialers: A rarity nowadays, but dialers connect to premium numbers or services, leading to unexpected charges or higher bills.
• Joke programs: Run harmless but annoying actions like fake error messages or silly pop-ups that disrupt normal use without causing permanent harm.

Notable examples of Potentially Unwanted Programs

Most PUPs don’t have memorable names. There are tools like System Cleaner Pro, PC Cleaner, or Registry Cleaner Pro that sound generic and helpful but end up installing extras or changing your settings. That said, there have been a few standouts, such as:

CCleaner

Once a popular system cleaner, it lost credibility after a version of the installer was compromised with malware. Moreover, its registry cleaning feature usually causes more problems than it solves, especially when people run CCleaner way too often and end up breaking Windows updates.

Beyond these incidents, the app just isn’t that useful. Modern Windows versions include built-in tools such as Disk Cleanup that perform the task without deleting important files.

JDownloader 2 with optional offers

JDownloader 2 is a free, safe download manager that lets you download files from hosting sites (a possible workaround to bypass the MEGA download limit).

However, its standard installer bundles optional third-party software that looks like adware and may get flagged as PUPs by antivirus tools. Fortunately, users can choose the alternative, adware-free installer to avoid unwanted extras.

uTorrent & qBittorrent

In 2021, torrent clients like qBittorrent and uTorrent were temporarily flagged by Windows’ security tools as potentially unwanted applications (PUAs). This was mostly because they can be used to download copyrighted or risky content.

Microsoft later removed the flag for consumer versions, but kept it in enterprise versions for added caution. That said, uTorrent includes in-app ads and still bundles optional PUPs with its installer, which Windows Defender detects as “PUABundler:Win32/uTorrent_BundleInstaller.”

Meanwhile, qBittorrent is open-source, ad-free, and doesn’t include any third-party bundles. It’s also secure as long as you stick to safe torrent sites and pair it with a secure VPN for torrenting.

What are the risks of PUPs?

While they’re not as dangerous as actual malware, PUPs can still be intrusive, cause performance issues, or make small dents in your finances, as seen below:

• Privacy and security risks: Trackware monitors your behavior and system information, while adware may inject malicious ads during browsing, even unintentionally. Similarly, browser hijackers can redirect you to websites you didn’t intend to visit, possibly with more sketchy app downloads.
• System slowdowns and annoyances: Cleaner and optimizer apps, along with other PUPs, can actually make your system run slower by using extra memory or CPU in the background, causing pop-ups, and interfering with everyday tasks.
• Hidden costs: Some PUPs push premium upgrades, subscriptions, or in-app purchases you didn’t intend to buy, or increase data usage that can affect mobile or metered connections.

How to tell if you have PUPs on your system

Here are some signs you may have potentially unwanted programs on your computer or mobile gadgets:

• Installed apps or extensions you don’t remember adding
• Security warnings from your browser or antivirus software about unwanted apps
• Noticeable drops in system performance
• Repeated pop-ups during normal system use
• Searches and links redirecting to unfamiliar sites
• Default search engine or homepage switching without your input
• Higher data use with no clear cause

How to protect against PUPs

PUPs can easily sneak onto your device if you’re not careful. Here are a few easy ways to keep your system clean:

• Download apps from trusted sources: Stick to official stores and known sites so installers don’t bundle extra junk alongside the app you actually wanted.
• Keep an eye out during setup: Slow down and read each screen so you can uncheck extra offers, toolbars, or permission requests the app doesn’t need to do its job.
• Have a trustworthy antivirus ready: Use a reliable antivirus to catch PUPs early and flag installers that try to add unwanted changes in the background.
• Don’t skip out on updates: Sure, Microsoft has a habit of breaking PCs thanks to rushed, vibe-coded Windows 11 updates. Still, it’s a good idea to update your system and apps to patch up security holes that PUPs may exploit to spy on you.
• Install an ad-blocker app or extension: Get rid of all the download managers, “PC cleaners,” or fake antivirus and VPN alerts designed to trick you into installing PUAs.
• Check your Android and iOS app permissions: Review what apps can access and remove permissions that feel excessive, especially for apps you rarely use.

How to get rid of PUPs: 9 useful tips

Fortunately, most PUPs can be removed without too much hassle. Follow this checklist to get rid of any unwanted apps.

1. Remove unfamiliar apps

Start by clearing out apps you don’t remember installing, as they may have come bundled with other software (like uTorrent or any free software with “optional extras”).

How to remove apps on Windows:

1. Search for Add or remove programs and click it.
2. Look for any unknown programs; you can sort by date installed to make things easier.
3. Click on the three horizontal dots to the right of the PUP.
4. Click Uninstall, then once again to confirm.

How to remove apps on Mac:

1. Open Finder and go to the Applications folder.
2. Look for apps you don’t recognize or remember installing.
3. Check inside the app folder in case it has a separate uninstaller. If not, just drag it to the Trash.
4. Empty the Trash to fully remove the app.

2. Disable unknown startup apps

Even after removing unwanted programs, some may leave behind residual startup entries. Checking these entries may also help you identify non-PUPs that slow down startup.

How to disable startup programs on Windows:

1. Look up Startup apps and open it.
2. Review the list and toggle off any entries you don’t recognize.
3. You can also click the little arrow button on the right to open the app’s location and check for leftover files.

How to disable startup apps on Mac:

1. Click the Apple menu and select System Settings.
2. Go to General > Login Items.
3. Select any unwanted program.
4. Click the minus (-) button to prevent it from running at startup.

3. Review your scheduled tasks and scripts

Some potentially unwanted programs on Windows stay active by running tasks or scripts that don’t appear in normal startup lists. Meanwhile, macOS uses so-called launch daemons and agents that can run independently of login items and may also be worth checking.

Only modify these system settings or delete files if you know what you’re doing.

How to check scheduled tasks on Windows:

1. Search for Task Scheduler and click to launch it.
2. Click Task Scheduler Library if it isn’t already highlighted.
3. Check for any strange tasks on the list in the middle, such as updates for apps that are no longer installed.
4. Right-click the task and click Disable.
5. You can also check your task history by selecting Task Scheduler (Local) on the left panel. Click the drop-down menu to view tasks from up to the past 30 days.

How to remove launch daemons and agents on Mac:

1. Open Finder and select your disk (usually Macintosh HD).
2. Go to Library and look for the LaunchAgents and LaunchDaemons folders.
3. If the folders are hidden, click Go in the Finder menu bar, hold down Option on your keyboard, and select Library.
4. Look through the .plist files in the folders and see if any have names linked to apps that still launch on startup, or are no longer installed.
5. Delete only the .plist files you’re sure are safe to remove.
6. Avoid deleting files in System/Library/LaunchAgents or System/Library/LaunchDaemons, as these are required for macOS to work.

4. Delete browser extensions you don’t recognize

Browser extensions can change your settings or inject ads without warning. Here’s how to remove malicious browser extensions on Chrome, Firefox, and Edge to stop these behaviors, prevent any potential tracking, and free up system resources.

5. Clear your browser cache and cookies

Clearing cache and site data removes old files and cookies that may keep unwanted settings or tracking info. Doing this after removing extensions or apps ensures that leftover data does not interfere with your browser or privacy. Here are a couple of guides for both:

• How to clear cookies on Chrome, Firefox, Edge, Safari, Opera, and mobile browsers
• How to clear cache on the same browsers

6. Reset your browser to default settings

This will restore your homepage, search engine, and other browser settings to their original state, and should also deal with any weird redirects or pop-ups. Useful in case removing extensions, PUPs, and clearing site data didn’t solve the issue on their own.

Here’s how to reset your settings in the most popular browsers.

Chrome

1. Launch Chrome and click the three-dot menu in the top-right corner.
2. Go to Settings > Reset settings > Restore settings to their original defaults.
3. Click Reset settings to confirm. This restores your Chrome homepage, search engine, pinned tabs, content settings, cookies, and extensions.

Firefox

1. Open Firefox and click the three-line button on the top-right.
2. Next, click Help > More troubleshooting information.
3. Click Refresh Firefox on the right, then once again in the prompt that appears. This keeps your bookmarks, passwords, cookies, and browsing history while removing extensions, themes, and other custom settings.

Edge

1. Open Edge and click on the three-dot button on the top-right.
2. Navigate to Settings > Reset settings > Restore settings to their default values.
3. Click Reset to confirm. Your startup page, new tab page, search engine, pinned tabs, and cookie data will be reset, while your extensions will be turned off.

7. Run a full antivirus scan

Scan the entire system with reputable antivirus software to check for harmful files, PUPs, and other threats. After the scan, follow the software’s prompts to delete or quarantine flagged items and stop them from reappearing later.

Now, this process may trigger false positives. For instance, some game modding tools inject code into game files, which antiviruses may see as malicious behavior. The same goes for .bat scripts that change the Windows registry or disable the usual bloatware. You’ll need to review flagged items carefully and only remove files you’re sure are unwanted or harmful.

8. Use a system backup to revert to an earlier state

Restoring your system via Windows Backup or the macOS Time Machine returns your device to a previous state before PUPs and any unwanted changes. Third-party cloud backup tools like Backblaze also allow for full system backups if you don’t want to rely on Microsoft or Apple’s built-in solutions.

9. Perform a full system reset if nothing else helps

A last resort when other methods fail to remove PUPs and other persistent problems, though it usually never comes to this unless you’re dealing with full-blown malware. Either way, a full reset lets you start fresh, restore personal files from backups, and reinstall only trusted software.

Potentially Unwanted Programs (PUPs) FAQs