diff --git a/libraries/src/Installer/InstallerAdapter.php b/libraries/src/Installer/InstallerAdapter.php
index 545092e0956fb..4fcd3947aadfd 100644
--- a/libraries/src/Installer/InstallerAdapter.php
+++ b/libraries/src/Installer/InstallerAdapter.php
@@ -185,6 +185,9 @@ protected function canUninstallPackageChild($packageId)
 	 */
 	protected function checkExistingExtension()
 	{
+		// Extension type is stored as lowercase on the #__extensions table field type
+		$this->type = strtolower($this->type);
+
 		try
 		{
 			$this->currentExtensionId = $this->extension->find(