Why Won't Internet Explorer 9 Install - Other Reasons
Among other reasons why Internet Explorer 9 won't install on your computer are:
1 Your computer does not meet the prerequisites for installing IE9
2 Installation of updates or a reboot is pending
3 Your antivirus software or firewall is blocking the installation
4 Your copy of IE9 installation package is corrupt
To know precisely why Internet Explorer 9 won’t install on your computer, you can turn off the antivirus and firewall temporarily and again try to install IE9. If it is installed without any problem, the antivirus or firewall was creating problem. Normally, this also applies to Internet Explorer 8. When you install IE8 or IE9, the installation package creates several temporary files. Your antivirus may treat these temporary files as malware and restricts access to them. This may result in no installation even though the installation might seem successful. Sometimes, the IE9 may be installed but would not work in such cases. I have always recommended users to turn off their antivirus and firewall while installing Internet Explorer, version 8 and 9.
If you have turned off the antivirus and still the Internet Explorer 9 won't install, chances may be that your computer is not ready for the browser. Check the prerequisites for installing IE9. You cannot install Internet Explorer 9 on Windows XP. Only the following operating systems accept it:
1 Windows Vista with Service Pack 2 (x86 and x64)
2 Windows 7 (x86 and x64)
3 Windows Server 2008 with Service Pack 2 (x86 and x64)
4 Windows Server 2008 R2 x64
If your computer meets the prerequisites and still Internet Explorer 9 won't install, check to see if there are any updates or a reboot pending. If yes, complete the updates' installation and reboot the computer before installing IE9.
If you still could not get Internet Explorer 9 to install on your computer, chances are that your installation package is corrupt. Download a fresh installation package and run the installer. I recommend downloading IE9 from Microsoft website. The linked website allows you to select your operating system and whether it is x86 or x64 before you click on Download.
This answers why won't Internet Explorer 9 install on your computer. If you still have doubts/questions, feel free to use the comment boxes.