diff --git a/contrib/win32/mercurial.iss b/contrib/win32/mercurial.iss
--- a/contrib/win32/mercurial.iss
+++ b/contrib/win32/mercurial.iss
@@ -83,6 +83,7 @@ Source: dist\w9xpopen.exe; DestDir: {app
 Source: dist\Microsoft.VC*.CRT.manifest; DestDir: {app}; Flags: skipifsourcedoesntexist
 Source: dist\library.zip; DestDir: {app}
 Source: dist\add_path.exe; DestDir: {app}
+Source: dist\cacert.pem; Destdir: {app}
 Source: doc\*.html; DestDir: {app}\Docs
 Source: doc\style.css; DestDir: {app}\Docs
 Source: mercurial\help\*.txt; DestDir: {app}\help
@@ -93,6 +94,7 @@ Source: COPYING; DestDir: {app}; DestNam
 
 [INI]
 Filename: {app}\Mercurial.url; Section: InternetShortcut; Key: URL; String: http://mercurial.selenic.com/
+Filename: {app}\Mercurial.ini; Section: web; Key: cacerts; String: {app}\cacert.pem
 
 [UninstallDelete]
 Type: files; Name: {app}\Mercurial.url
diff --git a/contrib/win32/win32-build.txt b/contrib/win32/win32-build.txt
--- a/contrib/win32/win32-build.txt
+++ b/contrib/win32/win32-build.txt
@@ -34,7 +34,7 @@ matching the mercurial version you want 
   Inno Setup
       http://www.jrsoftware.org/isdl.php#qsp
 
-      Get and install ispack-5.3.10.exe which includes Inno Setup Processor,
+      Get and install ispack-5.3.10.exe or later (includes Inno Setup Processor),
       which is necessary to package Mercurial.
 
   ISTool - optional
@@ -46,6 +46,9 @@ matching the mercurial version you want 
   Docutils
       http://docutils.sourceforge.net/
 
+  CA Certs file
+      http://curl.haxx.se/ca/cacert.pem
+
 And, of course, Mercurial itself.
 
 Once you have all this installed and built, clone a copy of the
@@ -73,7 +76,7 @@ Building instructions with MSVC 2008 Exp
     "C:\Program Files\Microsoft Visual Studio 9.0\VC\vcvarsall.bat" x86_amd64
     python setup.py py2exe -b 3
 
-Copy add_path.exe into the dist directory that just got created.
+Copy add_path.exe and cacert.pem files into the dist directory that just got created.
 
 If you are using Python up to version 2.5.4, copy mfc71.dll into the dist
 directory that just got created.