Whatever is the reason you want to uninstall IE9, here are the steps you can follow to uninstall IE9 from you machine using command prompt.
Steps to Uninstall IE9 :
Run command prompt by right clicking on its icon and selecting Run as Administrator ( see image ).
Close all running IE9 browser instances.
Paste below command at command prompt and press enter to execute
IE should get removed if you are having proper permissions on the system

Steps to Uninstall IE9 :
Run command prompt by right clicking on its icon and selecting Run as Administrator ( see image ).
Close all running IE9 browser instances.
Paste below command at command prompt and press enter to execute
FORFILES /P %WINDIR%\servicing\Packages /M Microsoft-Windows-InternetExplorer-*9.*.mum /c "cmd /c echo Uninstalling package @fname && start /w pkgmgr /up:@fname /quiet /norestart"
IE should get removed if you are having proper permissions on the system
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