Windows 7: Windows 7 Home Premium - suddenly boots longer

Hi everyone, A couple of days ago my laptop started to boot longer than it used to for the last six months. I have spent the last days searching for a solution and followed advices I have found. The boot time before the problem appeared was about 57 seconds, now it takes 120 seconds to boot up. I haven't installed any programs recently nor did I change anything in the autostart. What I did however, is upgraded Windows Defender and Live 2011 programs (10.23.2010). I uninstalled that upgrade (was only one with a matching date) but no improvement what so ever. I tried booting in diagnostic mode but with anti-virus program running and the computer booted like it used to in the good ol' days. Not sure what to do now... Any help would be really appreciated. Laptop: Acer Aspire 5740G Intel Core i5 430M 2.26 GHz ATI Radeon HD 5470M 4 GB RAM Avast! FREE Cheers

Follow instructions and this will help you diagnose
How to troubleshoot a problem by performing a clean boot in Windows Vista or in Windows 7

here is a tutorial that may help:

Beginners Guide to optimize Windows 7 for better performance | The Windows Club

Thanks guys. I plan on turning on and off services one by one. Hope I'll be able to find the one that causes the problem. Cheers

is this a clean install, in-place upgrade or factory install?

Uncheck everything in msconfig>startup except AV and gadgets.

Check the Event Viewer>Custom View>Admin log to google repeat errors to find how others have resolved them.

Install a lightweight free AV like MS security Essentials, which supplants Defender.

Run Driver Verifier to see if drivers are hanging: Using Driver Verifier to identify issues with Windows drivers for advanced users

Check the Performance log on Advanced Tools page accessed by clicking WEI score link at Computer>Properties. Look for cued issues at top of tools page, Generate A System Health Report.

Thanks Greg. I followed your advice and here's the update: All drivers are OK. I managed to find the service that was causing longer boot times, it was TrustedInstaller.exe I turned it off and the system boots a lot faster. Now my question is, how do I fix this exe? Also, it is a factory install with 5.7 WEI Score.

Unfortunately that is a major Windows 7 component so it may need repairing as it can't be turned off for long.

Try running SFC -SCANNOW Command - System File Checker or if necessary a Repair Install

A factory install in particular often needs a clean reinstall to overcome issues caused by the pre-installed factory bloatware. Clean Install Windows 7 after wiping the HD first: SSD - HDD Optimize for Windows Reinstallation

Many tech enthusiasts find a clean copy DVD installer for their version to reinstall using the Product Key on the COA sticker. Any retail installer can be unlocked to install your version: Universal Installation Disc - Create

You only need to do it once now as with built-in drive imaging you can save an image of the finished job to reimage the HD (or replacement) in 15 minutes. Backup Complete Computer - Create an Image Backup