--- a/toolkit/mozapps/update/updater/Makefile.in
+++ b/toolkit/mozapps/update/updater/Makefile.in
@@ -19,23 +19,22 @@ ifneq (,$(filter beta release esr,$(MOZ_
 else ifneq (,$(filter nightly aurora nightly-elm nightly-profiling nightly-oak nightly-ux,$(MOZ_UPDATE_CHANNEL)))
 	PRIMARY_CERT = nightly_aurora_level3_primary.der
 	SECONDARY_CERT = nightly_aurora_level3_secondary.der
 else
 	PRIMARY_CERT = dep1.der
 	SECONDARY_CERT = dep2.der
 endif
 
-CERT_HEADERS := primaryCert.h secondaryCert.h xpcshellCert.h
+CERT_HEADERS := primaryCert.h secondaryCert.h
 
 export:: $(CERT_HEADERS)
 
 primaryCert.h: $(PRIMARY_CERT)
 secondaryCert.h: $(SECONDARY_CERT)
-xpcshellCert.h: xpcshellCertificate.der
 
 $(CERT_HEADERS): gen_cert_header.py
 	$(PYTHON) $< $(@:.h=Data) $(filter-out $<,$^) > $@
 
 ifdef MOZ_WIDGET_GTK
 libs:: updater.png
 	$(NSINSTALL) -D $(DIST)/bin/icons
 	$(INSTALL) $(IFLAGS1) $^ $(DIST)/bin/icons

--- a/toolkit/mozapps/update/updater/archivereader.cpp
+++ b/toolkit/mozapps/update/updater/archivereader.cpp
@@ -14,17 +14,16 @@
 #include "nsAlgorithm.h" // Needed by nsVersionComparator.cpp
 #include "updatehelper.h"
 #endif
 
 // These are generated at compile time based on the DER file for the channel
 // being used
 #include "primaryCert.h"
 #include "secondaryCert.h"
-#include "xpcshellCert.h"
 
 #define UPDATER_NO_STRING_GLUE_STL
 #include "nsVersionComparator.cpp"
 #undef UPDATER_NO_STRING_GLUE_STL
 
 #if defined(XP_UNIX)
 # include <sys/types.h>
 #elif defined(XP_WIN)
@@ -67,29 +66,19 @@ VerifyLoadedCert(MarFile *archive, const
 */
 int
 ArchiveReader::VerifySignature()
 {
   if (!mArchive) {
     return ARCHIVE_NOT_OPEN;
   }
 
-  // If the fallback key exists we're running an XPCShell test and we should
-  // use the XPCShell specific cert for the signed MAR.
-  int rv = OK;
-#ifdef XP_WIN
-  if (DoesFallbackKeyExist()) {
-    rv = VerifyLoadedCert(mArchive, xpcshellCertData);
-  } else
-#endif
-  {
-    rv = VerifyLoadedCert(mArchive, primaryCertData);
-    if (rv != OK) {
-      rv = VerifyLoadedCert(mArchive, secondaryCertData);
-    }
+  int rv = VerifyLoadedCert(mArchive, primaryCertData);
+  if (rv != OK) {
+    rv = VerifyLoadedCert(mArchive, secondaryCertData);
   }
   return rv;
 }
 
 /**
  * Verifies that the MAR file matches the current product, channel, and version
  * 
  * @param MARChannelID   The MAR channel name to use, only updates from MARs