Windows 7 is remarkably secure and dependable. It's far from perfect, though. Here are six common Windows 7 disasters, and how to fix them.
4. No-one has the PC's Administrator password
If the wrong person leaves your company in a huff, one or more PCs could be left stranded. With no one in the company knowing the password to an administrator-level account, you can't install software, change important settings, or possibly access encrypted data. Fortunately, you can remove the password, letting you log on to that account. You do that with the Offline NT Password & Registry Editor, a bootable, text-based free program that you download as an .iso file. Double-click that file, and Windows 7 will start the process of burning it to a CD.
Boot the CD and follow these instructions. I've put the on-screen prompts in italics. After you type your answer, press Enter
boot: Just press Enter.
Select: : Above the prompt you'll see a list of hard-drive partitions. Select the right one by typing that number.
What is the path to the registry directory?...: The default is probably correct. Just press Enter.
What to do?  ->: 1
or simply enter the username...: Type the name of the administrator account. If you're not sure what it is, all of the account names are listed above the prompt.
Select: [q] >: 1
Select: ! - quit...: !
What to do : q
About to write file(s) back...: y
New run? [n]: n
Now remove the CD and reboot.
You should now be able to log on to the administrator account without a password. For security purposes, don't forget to create a new password for the account. Just be sure to remember what it is.
5. You think your PC is infected
Is your computer behaving oddly, slowing down at the wrong time, or refusing to run certain programs? It could be infected with malware. What can you do about that?
If your regular antivirus program - the one you already have up and running - hasn't stopped the questionable software, it probably can't. What you need is a second opinion - and possibly a third and a fourth.
Start with the free version of Malwarebytes Anti-Malware, a utility with an exceptional record of finding and removing malware. Download it, install it, launch it, update the database, and then perform a full scan.
Since installing and updating a cleaning utility are tasks that the infection may interfere with, it's a good idea to follow your Malwarebytes scan with other scans that don't require an installation or even an update.
On someone else's PC, download SuperAntiSpyware Portable and copy it to a flash drive. Boot the infected PC into Safe Mode, plug in the flash drive, and run the program. Since SuperAntiSpyware.com updates the portable program every day or two, you don't need to update it before the scan.
For a fourth opinion, try the F-Secure Rescue CD. This is another .iso file from which you can burn a bootable CD. Just boot from the CD and run the scan. The program will try to update its database over the internet. If it can't, you can download an update on another PC, put it on a flash drive, and keep that plugged in while running F-Secure on the infected PC.
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