Find and remove unwanted files in Windows with System Ninja

Before running a program such as System Ninja it is important to back up your PC – the program deletes files immediately, rather than sending them to the Recycle Bin. We will not be held responsible for accidentally deleted files, so proceed with caution. That warning out of the way, download System Ninja from the Web Atom website. When the page loads, click Maintenance at the top and choose System Ninja. At the next screen, click Download and then at the next screen, Download again. If the File Download Security Warning dialogue box appears, click Save and then choose a location for the downloaded file. Firefox users should select Save File to save the download to Firefox's default download folder. If you are prompted to update your copy of .NET at this stage, click Yes and follow the instructions. When the download has finished, locate the file and double-click to begin the installation. Follow the instructions and accept all the default settings. Once installed, click the Finish button to start the program.

When the program launches for the first time it looks like this. Junk Scanner is selected already. It's the first of the four options along the top and System Ninja highlights those file types it thinks can be removed safely down the right-hand side. These are typical junk – files stored in the temporary folders, cached files, icons that don't have any programs associated with them and so on. System Ninja scans only the disk it's installed on, so when ready, click the Scan Drive button to continue.

Depending on the size of the disk and the way it's organised, this first scan may take some time. When it has finished, System Ninja will return a list of results showing where the individual files are stored, their size and the kind of files that it has found. It's useful to click the Size heading once to sort files by how big they are and so that the largest are listed at the top. Despite our relatively good housekeeping, System Ninja found almost 900MB of junk on this disk – that's a sizeable chunk of wasted hard disk space.

Not sure about a particular entry? Right-click on the file name and choose Open Containing Folder from the pop-up menu. This opens the location in Windows Explorer. We know already from the file path that it's stored in a temporary folder but, if you are still uncertain, the best thing to do is create a new folder on the Windows Desktop and drag and drop a copy of the file into that before deletion. That way, if something goes wrong it can be reinstated later.

Alternatively, right-click on the file in System Ninja and choose the Analyze File option. This opens a new program window – the File Analyzer – that includes all sorts of information about the selected file. For example, we can see here that the last time it was accessed was when System Ninja scanned it. Before then, the last time it was touched was over a year ago, which is an indication (but only an indication) that it is a file we can do without.

Remember that System Ninja is a bit of a blunt instrument when it comes removing files. Its clear preference is to select and then remove everything. However, the Scan Settings on the right can be used to filter certain file types. If some of the results remain troubling, hold down Ctrl and left-click to deselect files in the results list. When done, click Clear Selected to delete your chosen files forever.

System Ninja reports back that the files have been deleted – click OK. Now let's try something else. Click to remove all the ticks from most of the file types on the right, leaving only Internet Cookies, History and Cache ticked. Then click the Scan Drive button again. If one of the web browsers System Ninja can identify (Chrome, Firefox, IE and Flock) is currently running, this warning message will appear. Click on the browser(s) in question, then click Close All Browsers and try again.

System Ninja can also manage programs that start automatically with Windows. Click the Startup Manager button at the top and have a look through the list there – yours will almost certainly be different from the one shown here. Some items are labelled clearly as being safe to remove (right-click and choose Remove Item) while others are not. A quick Google search usually sorts these ones out. On our PC, for instance, CTHelper is part of Creative Labs' sound card software and should probably be left alone.

Finally, there are always elaborate malicious software programs doing the rounds. A miscreant called Security Tool, for example, pretends to be a real anti-virus program but will actually restart your PC at regular intervals. If you get infected with one of these, System Ninja can help you regain control. Launch System Ninja and click the Process Manager button on the toolbar. If you spot the offender, tick it and click End Selected Process. If not, click the Run Tool button.

This will download a free companion product – Malrun Destroyer. When the System Ninja Downloader pops up click the Download button and when the program arrives, click OK and the Malrun Destroyer will run. Can't see it? That's because it runs minimised in a command line window. Just click the relevant Taskbar button and it will pop back onto the Desktop. With any luck you will see a message like this, giving your PC the all-clear. If Malrun finds anything, follow the instructions to remove it.