Why is my C drive full when I don’t have many apps installed?

It looks like your operating system might be using a lot of space, not just your installed apps. Windows can take up quite a bit of memory over time as it installs updates and system files. You mentioned thinking it might be a virus—just keep in mind that disk space alone isn't a clear indicator of malware. Have you tried disk cleanup? That can help you reclaim some space without wiping everything. If you really want to start fresh, a clean install of Windows might be necessary, but be sure to back up your files first!

You might want to double-check how much space your system is actually using. Sometimes system files and hidden files can take up a lot of space. If you’re low on space and can't even install small apps, that might indicate you have some large hidden files. Programs like Tree Size Free can help you discover what's really going on!

I recommend checking out tools like WizTree or WinDirStat. They can show you a visual representation of what's taking up space on your hard drive. This way, you can easily identify the big files or folders. Also, don’t worry too much about malware taking that much space; it's usually not the case. If you find something suspicious, you might consider a reinstall of Windows for a clean slate.