My computer is experiencing some odd behaviour where Windows hangs when attempting some operations. First, whenever I attempt to paste into some programs (e.g. Word, Excel) the program hangs. It doesn’t matter whether the Paste is being completed by the paste command or CTRL-V. However, the information can be pasted into other programs (e.g. WordPad, Eudora) without any issues. Second, right-clicking in Windows Explorer causes the program to hang. Third, launching some programs produces no apparent result. Checking Windows Task Manager will show the program process (e.g. winword) but not the actual application. Finally, the print command often causes the program to hang. Sometimes the entire computer just freezes necessitating a reboot of the computer, which will usually fix things until the next time. The computer is a Dell Dimension running Windows XP SP2 with all updates except Service Pack 2. There is no evidence of malware or viruses on the computer.

Problems where the computer is freezing in response to certain commands are always difficult to diagnose. Given the range of situations in which your computer appears to be freezing I would normally recommend that you backup all your important data then format your hard drive and reinstall Windows from scratch. However, we can try some alternatives before reaching this conclusion and taking such drastic action.

As a first step, we will determine whether the problem is being caused by some program running in the background and causing a conflict. To do this, we need to disable all programs from loading on startup and then check whether the problem continues. Go to the “Start” menu > “Run” and type “msconfig” (without the quotes) and click OK. The System Configuration Utility window should appear. This utility allows you to configure startup items which load upon Windows boot-up. Click the “Startup” tab. This will list all the programs and processes which run when Windows starts. Checked (ticked) entries indicate that the startup item is enabled (i.e. loads when Windows starts), and unchecked (unticked) items indicate that the startup item is disabled (i.e. does not load when Windows starts, as it has been disabled). Write down all the processes which are enabled (ticked). Then, disable all the processes by clicking the “Disable All” button. You should notice that all the startup items are now unchecked (unticked). Click OK and restart the computer. When the computer starts no programs or processes should load on startup. However, a message may appear informing you that you are running the computer in Selective Startup Mode. This simply indicates that not all startup options are enabled, because you have disabled some processes and programs from loading on startup. You can safely tick the option not to show this message again and click the OK button.

Once you are at the Windows desktop we now need to determine whether the problem continues. Try completing some of the operations which previously caused your computer to hang (e.g. right-click in Windows Explorer, pasting into Word, etc). If the problem does not continue, then it appears to have been caused by one of those programs or processes which loads on Windows startup. In this case, it is now a process of elimination to determine the particular program or process causing the problem. To do this, you will need to re-enable the startup processes one-by-one and then check each time whether the problem happens again. So, go into the System Configuration Utility (msconfig) and click the “Startup” tab. Using your written list of processes which were previously enabled, re-enable one of the processes and then click OK. Restart the computer, and check whether the problem continues. Should the problem not occur, then that process was not the one causing the problem. In this situation, repeat the procedure to re-enable another process. However, if the problem occurs then you have determined that the most recently enabled process is the one causing the problem. In this situation for the short-term you should leave that process disabled. However, this is not a long-term solution to the problem since you may wish to use the functionality or program associated with that disabled process. Therefore, we need to take some remedial action to get this process working again.

As a starting point, you need to determine what the process actually does and whether it is related to a particular program. If you cannot determine the purpose of the process from the process name then try searching Google or ProcessLibrary.com for the process name, as this should reveal the purpose of the process. Once this has been done, try reinstalling the program or application related to this process (as this should also remove and then reinstall the process itself). After the reinstallation, check whether the problem continues. If so, it would be worthwhile visiting the software manufacturer’s website to see whether any updated versions of the software package are available, as these updates or updated versions may resolve the problem. Should they not fix the problem, you may need to simply leave that process disabled.

In any case, make sure that once you have finished experimenting with the System Configuration Utility that you re-enable all the processes which were disabled during testing. If you forget to re-enable these processes then you may find that a lot of things stop working.

Should the above procedure not assist in tracking down the problem, and disabling all processes does not temporarily fix the problem, then it is possible there is something wrong with Windows itself. You have mentioned that all updates are applied except Service Pack 3. I strongly suggest that you apply Service Pack 3. There are several reasons for this advice. First, when Microsoft releases a Service Pack for Windows when you visit Windows Update the only available update listed will be that Service Pack. So, there may be additional updates required for your installation of Windows but you will not see these updates, or be provided with an opportunity to install the updates, until you install Service Pack 3. Second, installing the Service Pack may fix the problem if there is a corrupt file on the system, by providing a fresh and updated version of the file. Once you have installed Service Pack 3 make sure you revisit Windows Update to download any additional updates subsequent to Service Pack 3.

If installing Service Pack 3, and any subsequent updates, does not fix the problem then you should try running the Windows System File Checker (SFC) utility. This will check Windows for any corrupt or missing system files and replace them with known good copies. To start the System File Checker go to the “Start” menu > “Run” and type “sfc /scannow” (without the quotes) and click OK. The SFC utility will commence operation immediately. Once it has finished it will exit silently with no user feedback. At this point you can restart the computer and check whether the problem persists.

Should running the System File Checker utility not resolve the problem then it seems that your best option to reach a speedy resolution will be to reinstall Windows. While this is not the most convenient option, it should definitely fix the problem. In such situations the problem could really be caused by any number of other factors, and it is a known fact that after having a Windows installation which is several years old the build-up of old files and registry entries on the computer takes a large performance toll, often also resulting in instability. I would not be surprised if that is the problem you are currently experiencing.

Before embarking on the reinstallation procedure you need to backup any data you wish to keep. This is essential as you will lose all data on your computer, as the reinstallation will be a data destructive process. I suggest that you backup all data you need to keep (e.g. documents, email, etc) to an external hard drive. This provides the most convenient method of backup, and is also very cost effective as you should be able to purchase a drive which can store all your data for around $100 – $150. Depending on the critical nature of the data on your computer, you may wish to backup your data to a second device. Whenever I complete a reinstallation of Windows I make sure that I have two backups of all my data. Generally one backup is my normal regular system backup which runs every hour daily (I am using Time Machine on Mac OS X to do my regular daily backups, but similar systems exist with software such as the Windows Backup utility or Acronis True Image Home as covered in previous columns). Then I also do a special one-off copy of all my data onto another external hard drive. This is the backup I restore from when copying my data back onto the new Windows installation, and the other backup is purely a reserve in case something goes horribly wrong with the primary backup (which has fortunately not happened yet).

Once you are certain that all the data you need to keep has been backed-up, restart the computer and boot from your Windows XP CD. Follow the prompts to commence a fresh installation of Windows and elect to format the hard drive prior to installation. This will ensure that the previous installation of Windows is removed and the fresh installation is copied. Once the installation has concluded and Windows is booted, you can copy the backed-up data back onto the system.