diff --git a/Uninstall-MSI.ps1 b/Uninstall-MSI.ps1
index f9be12f..e5bb31f 100644
--- a/Uninstall-MSI.ps1
+++ b/Uninstall-MSI.ps1
@@ -4,6 +4,13 @@
 $UNINSTALL_KEYS = Get-ChildItem -Path HKLM:\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall
 $UNINSTALL_KEYS += Get-ChildItem -Path HKLM:\SOFTWARE\WOW6432Node\Microsoft\Windows\CurrentVersion\Uninstall
 
+Function Get-GUIDFromMSIUninstallString {
+    param([string]$str)
+    $start = $str.IndexOf('{') + 1
+    $end = $str.IndexOf('}')
+    Return $str.Substring($start, $end - $start)
+}
+
 Foreach ( $reg in $UNINSTALL_KEYS ) {
     ## Get the uninstall key
     $REG_PROPERTY = Get-ItemProperty -Path $reg.PSPath
@@ -19,10 +26,10 @@ Foreach ( $reg in $UNINSTALL_KEYS ) {
             If ( $REG_PROPERTY.InstallLocation ) { $INSTALL_LOCATION = $REG_PROPERTY.InstallLocation }
 
             ## Get the product code from the UninstallString
-            If ( $REG_PROPERTY.UninstallString ) { $PRODUCT_CODE = $REG_PROPERTY.UninstallString.Replace('MsiExec.exe /X','') }
+            If ( $REG_PROPERTY.UninstallString ) { $PRODUCT_CODE = $(Get-GUIDFromMSIUninstallString -str $REG_PROPERTY.UninstallString) }
 
             ## Get the product code from the ModifyPath
-            ElseIf ( $REG_PROPERTY.ModifyPath ) { $PRODUCT_CODE = $REG_PROPERTY.ModifyPath.Replace('MsiExec.exe /X','') }
+            ElseIf ( $REG_PROPERTY.ModifyPath ) { $PRODUCT_CODE = $(Get-GUIDFromMSIUninstallString -str $REG_PROPERTY.ModifyPath) }
 
             ## Uninstall the app
             If ( $PRODUCT_CODE ) {