As a convenience to new users who are unfamiliar with which files they should 
and should not distribute, the Inno Setup compiler will display an error _
  message if one 
attempts to install certain "unsafe" files using the [Files] section. These _
files are listed 
below.
 
(Note: It is possible to disable the error message by using a certain flag on _
  the [Files] 
section entry, but this is NOT recommended.)
 
Any DLL file from own Windows System directory 
You should not deploy any DLLs out of your own Windows System directory because 
most of them are tailored for your own specific version of Windows, and will _
  not work 
when installed on other versions. Often times a user's system will be rendered 
unbootable if you install a DLL from a different version of Windows. Another _
  reason why 
it's a bad idea is that when you install programs on your computer, the DLLs 
' may be 
replaced with different/incompatible versions without your knowledge. This _
  could lead 
to unexpected and difficult-to-trace problems on users' systems when you build 
' new 
installations.
 
Instead of deploying the DLLs from your Windows System directory, you should _
  find 
versions that are specifically deemed "redistributable". Redistributable DLLs _
typically 
work on more than one version of Windows. To find redistributable versions of _
the 
Visual Basic and Visual C++ run-time DLLs, see the Inno Setup FAQ.
 
If you have a DLL residing in the Windows System directory that you are _
  absolutely sure 
is redistributable, copy it to your script's source directory and deploy it 
' from there 
instead.
 
ADVAPI32.DLL, COMDLG32.DLL, GDI32.DLL, KERNEL32.DLL, RICHED32.DLL, 
SHELL32.DLL, USER32.DLL, UXTHEME.DLL 
 
These are all core components of Windows and must never be deployed with an 
installation. Users may only get new versions of these DLLs by installing a new _
  version 
of Windows or a service pack or hotfix for Windows.
 
(Special case) COMCAT.DLL, MSVBVM50.DLL, MSVBVM60.DLL, OLEAUT32.DLL, 
OLEPRO32.DLL, STDOLE2.TLB 
 
If DestDir is set to a location other than {sys} and the regserver or _
  regtypelib flag is 
used, then the above files will be considered "unsafe". These files must never _
be 
deployed to and registered in a directory other than {sys} because doing so can 
potentially cause all programs on the system to use them in favor of the files _
  in {sys}. 
Problems would result if your copies of the files are older than the ones in _
{sys}. Also, if 
your copies of the files were removed, other applications would break.
 
COMCAT.DLL version 5.0 
Version 5.0 of COMCAT.DLL must not be redistributed because it does not work on 
Windows 95 or NT 4.0. If you need to install COMCAT.DLL, use version 4.71 _
  instead.
 
COMCTL32.DLL 
Microsoft does not allow separate redistribution of COMCTL32.DLL (and for good 
reason - the file differs between platforms), so you should never place _
  COMCTL32.DLL 
in a script's [Files] section. You can however direct your users to download the 
COMCTL32 update from Microsoft, or distribute the COMCTL32 update along with _
  your 
program.
 
CTL3D32.DLL, Windows NT-specific version 
Previously, on the "Installing Visual Basic 5.0 & 6.0 Applications" How-To page _
  there 
was a version of CTL3D32.DLL included in the zip files. At the time I included _
it, I was 
not aware that it only was compatible with Windows NT. Now if you try to _
install that 
particular version of CTL3D32.DLL you must use a MinVersion setting that limits _
it to 
Windows NT platforms only. (You shouldn't need to install CTL3D32.DLL on Windows 
95/98/Me anyway, since all versions have a 3D look already.)
 
SHDOCVW.DLL, SHLWAPI.DLL, 
=> URLMON.DLL[u], 
WININET.DLL 
These are core components of Internet Explorer and are also used by Windows 
Explorer. Replacing them may prevent Explorer from starting. If your application 
depends on these DLLs, or a recent version of them, then your users will need to 
install a recent version of Internet Explorer to get them.
 
MSCOREE.DLL 
This file is part of the Microsoft .NET Framework. You cannot safely install or _
  update 
the .NET Framework by including this file with your installation. Call or _
direct your users 
to dotnetfx.exe instead.

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