diff --git a/xpinstall/src/nsInstallResources.cpp b/xpinstall/src/nsInstallResources.cpp
index ab1c541df449..99d40d248c05 100644
--- a/xpinstall/src/nsInstallResources.cpp
+++ b/xpinstall/src/nsInstallResources.cpp
@@ -62,7 +62,7 @@ static nsXPIResourceTableItem XPIResTable[] =
     { "WindowsShortcut",       "Windows Shortcut: %s" },
     { "MacAlias",              "Mac Alias: %s" },
     { "WindowsRegisterServer", "Windows Register Server: %s" },
-    { "UnknownFileOpCommand",  "Unkown file operation command!" },
+    { "UnknownFileOpCommand",  "Unknown file operation command!" },
 
     // XXX FileOp*() action strings
     // XXX WinReg and WinProfile action strings