QUESTION I reorganised some files on my Windows Vista Home Basic PC and am now receiving a full-disk warning. The drive has two 67GB partitions. I moved 40GB of files to D, leaving 31GB on C. I unsuccessfully attempted to delete the Winsxs file, which hogs 12GB. I’ve also removed 3GB of programs. But every time I reboot, the capacity used on C is still 31GB. Doug Pyburn

HELPROOM ANSWER A basic installation of Vista will gobble up 15GB of drive space before you’ve even installed any software or downloaded any patches, service packs or Windows Update files. It’s also possible that your pagefile (virtual memory) is set too large, or you have a faulty program generating masses of temporary files or a disk error. Windows hibernation files can also grow very large, so make sure you’re turning off the PC using the Shut Down option rather than Sleep.

Don’t delete any content from the Winsxs folder. This holds important files that are required for the correct operation of Windows and your installed software.

Let’s do some housekeeping and clear up what we can. Download and run CCleaner. You’ll need to close your web browser first.

Next, move your pagefile to another partition. The pagefile can grow and grow if it isn’t kept under control. Right-click Computer, Properties, Advanced System Settings, Performance, Advanced, Virtual Memory, Change. Highlight your second drive partition and tick the 'System Managed Size’ option. Next, highlight your C partition and select ‘No paging file’, Set, ok. Finally, reboot the machine.

Now let’s shrink or delete the hibernation file. Go to Control Panel, Folder Options, View and select ‘See hidden files, folders and drives’. Clear the option to ‘Hide protected hidden operating system files’, then click Apply. Next, double-click the C partition in Computer and jot down the size of the hiberfil.sys and pagefile.sys files (you may need to hover the cursor over it or right-click it and choose Properties).

To delete the Hibernation option, go to Start, All Programs, Accessories. Right-click Command Prompt and select ‘Run as administrator’. When the command prompt box opens, type powercfg –h and press Enter. You may have to manually delete the hiberfil.sys file, however.

To shrink the hibernation file, open the command prompt and type powercfg -h -X (where X is the percentage of the original size – for example, powercfg -h -75 reduces the file to 75 percent of the original) and press Enter. The smallest you can go is 50 percent.

Windows Update files are another disk hog, but you’ll need to stop the Automatic Updates service before you can delete them. Right-click Computer and choose Manage, Services and Applications, Services. Right-click Windows Update and select Stop.

Navigate to C:\Windows and delete the SoftwareDistribution folder. It will be recreated (but empty) the next time you reboot the PC. Remember to restart Automatic Updates afterwards.

You should also check your drive for errors, since the ‘free space’ information reported may be incorrect. Right-click the C partition in Computer and choose Properties, Tools, Error Checking. Tick the ‘Automatically fix file system errors’ option, press Start and reboot when prompted.

To complete the cleanup process, defragment your drive. Click Start, Search, type disk and select Disk Defragmenter. Choose the C drive, then ‘Defragment disk’.

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