diff --git a/Docs/src/usefulfunc.but b/Docs/src/usefulfunc.but
index d9bacd77..1599b9a1 100644
--- a/Docs/src/usefulfunc.but
+++ b/Docs/src/usefulfunc.but
@@ -486,7 +486,7 @@
 \c
 \c    !ifndef UPGRADEDLL_NOREGISTER
 \c      WriteRegStr HKLM "Software\Microsoft\Windows\CurrentVersion\RunOnce" \
-\c      "Register ${DESTFILE}" '"$SYSDIR\rundll32.exe" "${DESTFILE},DllRegisterServer"'
+\c      "Register ${DESTFILE}" '"$SYSDIR\rundll32.exe" "${DESTFILE}",DllRegisterServer'
 \c    !endif
 \c
 \c    Goto "done_${LOCALFILE}"