Tuneup Utilities is a tweaking suite. Win7 is too lean to tolerate compound tweaking - it will almost always mess up your system in short order as seen here regularly. If you have been tweaking Win7 beyond normal System settings, try to System Restore to before you got tweaky to see if you can recover.
Otherwise work through these standard
troubleshooting steps:
Study the Event Viewer>Custom>Admin view for repeat errors to google text and ID# for resolution. Check also the Performance log on Advanced Tools page accessed by clicking your WEI score link at Computer>Properties. Check for cued issues at top of Tools page, Generate A System Health Report.
Look for issues cued in Action Center in System Tray. Type "Solutions" in Start Search box to see if any have been sent for Problems reported or not. Always report problems when asked as Win7 is interactive this way.
Check for infection by installing
Malwarebytes, update, run a Full Scan. Many issues can be solved by running a free lightweight AV like MS Security Essentials or Avast 5 with the Win7 Firewall for best performance. 32 bit Avast 5 will give you a deep boot scan.
Test your hardware by running memtest86 CD for 5-6 passes or overnight:
RAM - Test with Memtest86+, then test the HD using maker's diag/repair full CD scan:
Hard Drive Diagnostics Tools and Utilities (Storage) - TACKtech Corp..
Check temps for overheating by installing SpeedFan, blow dust out of the case using canned air, check all connections carefully avoiding static discharge to components by touching case first, reseat RAM.
Turn off all Startup items except AV and gadgets:
Startup Programs - Change. After Restart, in msconfig>Services "Hide All MS Services" to see what is running without your knowledge. Turn it off in it's program Preferences or uninstall.
Check for any errors in Device Manager. If you are using the chipset given by the Win7 installer, try the manufacturer's latest from the Support downloads webpage for your model computer or mobo.
Driver Install - Device Manager - Windows 7 Forums
Check for newer display driver, or roll back to the previous verison. Turn off or uninstall the accompanying software package.
Some of these steps suggested for
cleaning up a factory bloatware install might help.
Run
SFC /SCANNOW Command - System File Checker to repair any damaged or corrupt OS files.
As a last resort before reinstall try a
Repair Install which can fix most problems as it reinstalls the OS while keeping all programs, files and settings in place.
Tips for a clean reinstall, which is actually better than getting a new computer with today's bloated factory pre-installs.
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