diff --git a/tools/msi/janet.wxs b/tools/msi/janet.wxs
index bbf62066..9ea2038d 100644
--- a/tools/msi/janet.wxs
+++ b/tools/msi/janet.wxs
@@ -159,6 +159,7 @@
             <Condition>ALLUSERS=1</Condition>
             <Environment Id="PATH_PERMACHINE" Name="PATH" Value="[BinDir]" Action="set" Permanent="no" System="yes" Part="last"/>
             <Environment Id="JANET_BINPATH_PERMACHINE" Name="JANET_BINPATH" Value="[BinDir]" Action="set" Permanent="no" System="yes"/>
+            <Environment Id="JANET_MANPATH_PERMACHINE" Name="JANET_MANPATH" Value="[DocsDir]" Action="set" Permanent="no" System="yes"/>
             <Environment Id="JANET_PATH_PERMACHINE" Name="JANET_PATH" Value="[LibraryDir]" Action="set" Permanent="no" System="yes" />
             <Environment Id="JANET_HEADERPATH_PERMACHINE" Name="JANET_HEADERPATH" Value="[CDir]" Action="set" Permanent="no" System="yes"/>
             <Environment Id="JANET_LIBPATH_PERMACHINE" Name="JANET_LIBPATH" Value="[CDir]" Action="set" Permanent="no" System="yes"/>
@@ -167,6 +168,7 @@
             <Condition>NOT ALLUSERS=1</Condition>
             <Environment Id="PATH_PERUSER" Name="PATH" Value="[BinDir]" Action="set" Permanent="no" System="no" Part="last"/>
             <Environment Id="JANET_BINPATH_PERUSER" Name="JANET_BINPATH" Value="[BinDir]" Action="set" Permanent="no" System="no"/>
+            <Environment Id="JANET_MANPATH_PERUSER" Name="JANET_MANPATH" Value="[DocsDir]" Action="set" Permanent="no" System="no"/>
             <Environment Id="JANET_PATH_PERUSER" Name="JANET_PATH" Value="[LibraryDir]" Action="set" Permanent="no" System="no" />
             <Environment Id="JANET_HEADERPATH_PERUSER" Name="JANET_HEADERPATH" Value="[CDir]" Action="set" Permanent="no" System="no"/>
             <Environment Id="JANET_LIBPATH_PERUSER" Name="JANET_LIBPATH" Value="[CDir]" Action="set" Permanent="no" System="no"/>