STSADM command operations to install feature / uninstall feature
To Uninstall feature
stsadm -o uninstallfeature -filename filename or -name featurefoldername or -id featureID
Eg., filename as valid file path, such as "MyFeature\Feature.xml".
To install feature
stsadm -o installfeature -filename filename or -name featurefoldername
Eg., filename as valid file path, such as "MyFeature\Feature.xml".