Thousands of CCleaner users are expressing outrage after discovering that Avast antivirus software has been installing itself on their computers without explicit permission, transforming what should be an optional add-on into what many are calling a deceptive practice.
The controversy takes on added significance given Avast’s documented history of collecting and selling user data through its antivirus software.
The issue centers on CCleaner, a popular system optimisation tool that was acquired by cybersecurity company Avast.
Since the acquisition, users have reported a disturbing trend: the antivirus program appears on their systems after CCleaner installations or updates, even when they specifically tried to avoid it.
A Company with a Troubled Privacy Record
The unwanted installations are particularly concerning given revelations about Avast’s data collection practices. In 2020, a joint investigation by Motherboard and PCMag exposed how Avast had been harvesting and selling detailed user browsing data through a subsidiary called Jumpshot.
According to the investigation’s findings, the Avast antivirus program installed on users’ computers collected extensive data about their internet activity.
Jumpshot repackaged the data into products sold to major corporations worldwide. Its clients included Google, Yelp, Microsoft and McKinsey, along with brands such as Pepsi, Sephora, Home Depot, Condé Nast and Intuit.
Some of these clients reportedly paid millions of dollars for products including a so-called “All Clicks Feed” that could track user behavior, clicks, and movement across websites in highly precise detail.
The investigation revealed documents showing the extensive scope of this data collection and monetization operation, raising serious questions about user privacy and consent.
Following the exposure, Avast announced it would shut down Jumpshot’s operations. However, the revelation damaged the company’s reputation and left many questioning whether they wanted Avast software on their computers at all—making the current unauthorized installations even more problematic.
The Hidden Installation Problem
The installation controversy has been building for years, with users flooding support forums with complaints.
Many describe identical experiences: they update or install CCleaner, only to discover Avast antivirus running in the background shortly after, complete with desktop icons and system processes they never authorised.
According to company representatives, Avast is supposed to be offered as an optional component during CCleaner installation, with users seeing a consent screen where they can decline the additional software.
However, numerous users report that this checkbox either doesn’t appear at all, is hidden within nested customisation menus, or installs the software even when users believe they’ve opted out.
The problem appears particularly prevalent during CCleaner updates. Users who have been running CCleaner without issue suddenly find Avast installed after a routine update, despite never agreeing to add new software to their system.
Some report that updates run automatically in the background while they’re working, and they only discover the unwanted antivirus installation hours or days later when they notice unfamiliar processes running or new icons on their desktop.
Technical Excuses and Ongoing Issues
A CCleaner product manager acknowledged that problems exist, though the company maintains installations should be voluntary.
Technical investigations reportedly revealed cases where high system load could delay the consent screen from displaying, allowing the installation to proceed automatically.
The company claims to have addressed some issues in subsequent updates, but complaints have continued well beyond those supposed fixes.
Users report the problem occurring across multiple versions of CCleaner, suggesting either inadequate solutions or insufficient priority given to resolving the issue.
The bundling controversy has been ongoing since at least 2018 when Avast was first integrated into CCleaner version 5.37.
User reports describe various scenarios—fresh CCleaner installations, automatic background updates, and manual updates where they specifically looked for and couldn’t find an opt-out option.
A Violation of User Trust
The situation is particularly troubling given that CCleaner is designed to remove unwanted software and optimise system performance—yet it’s now being accused of installing unwanted programs itself.
For users who deliberately avoid certain antivirus solutions, especially those with known data collection practices, or who already have security software configured to their preferences, the unauthorized installation creates conflicts and confusion.
More Than Simple Bloatware
Unlike a web browser or cloud storage tool, antivirus programs integrate deeply into system operations, run constantly in the background, monitor all file and network activity, and can significantly impact computer performance.
More critically, given Avast’s history of data collection, users who have deliberately chosen not to install Avast are now finding it on their systems anyway—potentially collecting browsing data and system information they never consented to share.
Users who specifically choose CCleaner for system cleaning may feel misled when their choice results in additional software they didn’t want, especially when that software comes from a parent company with a documented history of monetising user data.
The irony of a “cleanup” tool installing software that some consider privacy-invasive is not lost on frustrated users.
Does CCleaner Actually Work?
Such programs are largely ineffective, claiming to clean up registry entries that neither improve performance nor slow down a PC if left untouched.
In practice, outdated registry entries cause no harm, and for most other functions, Windows already provides built-in tools that handle these tasks just as effectively.
At this point, the app feels less like a utility and more like a delivery system for bloatware. What’s marketed as “system optimisation” increasingly appears to be a gateway for quietly pushing unwanted software onto users’ machines, eroding trust and offering little real value in return.
Optimise Windows And Cleanup – Without CCleaner
Here are practical, built-in ways to optimise and clean up Windows without using third-party tools like CCleaner (Bloatware Apps)
1. Use Windows Storage Cleanup
- Go to Settings → System → Storage
- Enable Storage Sense
- Click Temporary files and remove:
- Temp files
- Windows Update cleanup
- Recycle Bin contents
2. Uninstall Unused Programs
- Settings → Apps → Installed apps
- Remove software you no longer use
- This has far more impact than any “registry cleaner”
3. Disable Unnecessary Startup Apps
- Press Ctrl + Shift + Esc to open Task Manager
- Go to the Startup tab
- Disable apps you don’t need launching at boot
4. Clean Temporary Files Manually
- Press Win + R, type
%temp%, press Enter - Delete all files you can
- Repeat with:
tempprefetch(skip files that won’t delete)
5. Run Disk Cleanup
- Press Win + R, type
cleanmgr - Select your system drive
- Click Clean up system files
- Remove old update files and system logs
6. Optimise Drives (SSD/HDD)
- Search Defragment and Optimise Drives
- For HDDs: run Defragment
- For SSDs: Windows automatically handles optimisation (TRIM)
7. Check for Malware Using Windows Security
- Open Windows Security
- Run a Full Scan
- Avoid third-party “cleanup” or “boost” tools
8. Update Windows and Drivers
- Settings → Windows Update
- Keep the OS and drivers current for stability and performance
9. Leave the Registry Alone
- Windows safely ignores old registry entries
- Cleaning them does not improve speed
- Registry cleaners often cause more problems than they solve
Widespread Abandonment
The controversy has driven longtime CCleaner users to abandon the software entirely. Online discussions show users sharing alternatives and warning others about the installation behavior.
For Avast, a company already recovering from a major privacy scandal, the continued reports of sneaky installations suggest a pattern of prioritising business interests over user consent—a pattern that appears to be costing them the trust and loyalty of their user base.
Since Avast acquired Piriform, the developer of CCleaner, user dissatisfaction has steadily grown among what was once a 130-million-strong user base. Many users report that CCleaner installs Avast antivirus without clear consent, raising serious concerns.
From version 5.37 released in August, Avast was bundled into CCleaner installs, and despite being labelled as opt-out, many users say the process is misleading and effectively forces installation.
Tech Business News first became aware of the issue when Avast Antivirus installed itself on it’s editorial PC without knowledge or consent, despite the system already running a paid and more ethically positioned security solution, Bitdefender.
