# How can I tell what version of IIS is installed?

I've got a box running Win2k3 and some directions from Microsoft KB about SSL certificates, for IIS 5.0 and 6.0. How can I tell which version of IIS is currently installed?

-

As a more general answer, not specifically aimed at your question, Microsoft has a support article which lists all of the versions and the operating systems that provide each one.

-
Yah, that was the page I was looking for! :) +1 – squillman May 20 '09 at 20:07
Unfortunately Microsoft haven't yet updated that page to include IIS 7.5. Here's an alternative reference which does include it: en.wikipedia.org/wiki/Internet_Information_Services – JV01 Feb 7 '11 at 13:45
@JV01, (Due to this page getting 100k+ of views....) It has already been updated to version 8.0. – Pacerier Aug 14 '15 at 4:56
Well yes, but now the MS article doesn't include IIS 8.5 or IIS 10 (the latter is included in Windows Server 2016 and Windows 10). Always a step or two behind... – JV01 Aug 19 '15 at 10:33

You can look at %SYSTEMROOT%\system32\inetsrv\inetinfo.exe. Right-click and get properties, click the Version tab.

You can also look at an HTTP response header

1. telnet mywebserver 80
2. type in HEAD / HTTP/1.0 [enter][enter]
3. Look at the line that starts with Server:
-
Interesting; it claims version 6.0. – jldugger May 20 '09 at 20:06
On XP Pro?? Never seen that... Mines says 5.1. – squillman May 20 '09 at 20:12
@jldugger: I doubt it. I tried to telnet 80 a XP machine. It's 5.1. You must have been connected to a Windows 2003 server. (typo in server name?) – splattne May 20 '09 at 20:16
We're all kinds of crazy around here. A few comments about your edit: 1. I think there's an unallowed space between / and HTTP 2. It just returns the normal HTML webpage; were you expecting something different? – jldugger May 20 '09 at 20:18
On Windows 2012 R2, there is no inetinfo.exe in %SYSTEMROOT%\system32\inetsrv. But the telnet method works. – Joe White Feb 9 '15 at 18:34

Windows XP has IIS 5.1 installed, so use the IIS 5.0 procedure. See this article for an overview of IIS 5.1:

A look at IIS 5.1 in XP Pro - What's different from IIS 5?

IIS 5.1 is a feature only to be found on Microsoft's XP Pro operating system. It is not installable (reliably) on XP Home. Additionally, there are no plans to update IIS 5.0 on Windows 2000 to IIS 5.1.

IIS 5.1 is basically the same engine as IIS 5.0 but since XP is a client operating system, it has the built in limits that are customary for Microsoft’s client operating systems—such as connection limits and only one Web site. Even though based on IIS 5, there are significant differences from IIS 5.0 that you should know about.

You could also open a page in the browser which runs this simple asp Script:

<%
response.write(Request.ServerVariables("SERVER_SOFTWARE"))
%>


As a side note: it is interesting that IIS (beginning with Windows Server 2000/version 5.0) can't be upgraded without upgrading the operating system. Every Windows version has it's own IIS version:

Windows NT 3.51          1.0
Windows NT 4             2.0-4.0
Windows Server 2000      5.0
Windows XP Professional  5.1
Windows Server 2003      6.0
Windows Vista            7.0
Windows Server 2008      7.0
Windows Server 2008 R2   7.5
Windows 7                7.5
Windows Server 2012      8.0
Windows 8                8.0
Windows Server 2012 R2   8.5
Windows 8.1              8.5

-
"only one Web site". Does that include Microsoft SharePoint Administration? Because if not, then there's clearly two websites running. – jldugger May 20 '09 at 20:07
Try to add more that to web site (not virtual directory or web apps under the default web in IIS 5.1 on Windows XP). You can't do that. – splattne May 20 '09 at 20:12
Server 2008 R2 7.5 – Saariko Aug 16 '12 at 6:41
@Saariko thank you! I've updated the list. – splattne Aug 16 '12 at 7:48
IIS 7.5 Express can run on Windows XP and above while IIS 8.5 Express can run on Windows Vista SP1 and above - microsoft.com/en-us/download/details.aspx?id=1038 & microsoft.com/en-us/download/details.aspx?id=34679 – mvark Jun 13 '14 at 10:16

When you have IIS Manager open, you can click Help -> About to see the version.

-
Great answer. However, it's easy to miss the real IIS version and instead see only the version number for the actual IIS Manager. E.g., on my Windows 8.1, when I bring up that Help > About box, it would be easy to mistakenly read the version of IIS as 6.2. So I've added a screenshot to clarify where the real version number is. – Charles Roper Mar 24 '15 at 22:49

You should be able to determine the IIS version number from the following registry value: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\InetStp\VersionString

This shows "Version 6.0" on my local machine.

(You can find details on how to open regedit to view this from http://www.wikihow.com/Open-Regedit)

-
Works, but do you have an official source for it? Otherwise, such reverse engineering will seriously break in the future. – Pacerier Aug 14 '15 at 5:15
I'm not sure how this could "seriously break". We're trying to find out which version of IIS is being used - not control a nuclear power station! 😉 – Jonathan Williams Aug 14 '15 at 14:30

Just as a fun data point:

From 32-bit land:

Windows XP ships with IIS 5.1.

Windows Server 2003 with IIS 6.0.

But the x64 edition of Windows XP is based on the Windows Server 2003 SP1 codebase, and the version of IIS included in Windows XP Professional X64 Edition is IIS 6.0.

Crazy stuff, I know.

-

If you have no access what so ever to the back end of a machine you can try using NetCraft such as http://toolbar.netcraft.com/site_report?url=http://www.starbucks.com

There are enough little finger prints on the headers the machine gives off, that they can usually identify the signature of the machine, unless someone alters them on purpose.

-

If you have curl and grep installed, e.g. through Cygwin, or from another machine running OS X or Linux, you can use the power of command line tools and avoid knowing where exactly to click in which situation:

 \$ curl --silent -I http://example.com/|grep Server
Server: Microsoft-IIS/8.5

-

On the Uninstall Programs window in Windows 10:

-

Very simple to know the IIS Version installed on your system.

Simple type localhost on your browser and enter you are able to see the IIS version.

-