The CTP3 of SQL Server Code-Named "Denali" is now available. You can download the bits here:

 
<a href="http://www.microsoft.com/betaexperience/pd/SQLDCTP3CTA/enus/default.aspx" title="http://www.microsoft.com/betaexperience/pd/SQLDCTP3CTA/enus/default.aspx" target="_blank" rel="noopener noreferrer">Download SQL Server "Denali" CTP3</a>
<i>(You will need to use File Transfer Manager on Windows, and a Java applet on Mac OS.)  </i>

If you are just interested in the Express version, you can go here (no FTM required):

Download SQL Server "Denali" Express CTP3

There were release notes available last week, but they were taken down when they became too publicized. They have been made available again:

http://social.technet.microsoft.com/wiki/contents/articles/3711.aspx

Right now, after the download starts, you will see this:

But that link just leads to the SQL Server Learning Center, which still only has information on 2005, 2008 and 2008 R2. 

In the meantime, I've assembled my own release notes for you, summarizing some of the more salient points, adding my own two cents where appropriate, and leaving out several of the obscure issues that are unlikely to affect a large number of users. I will follow up with my install experiences (I posted a setup walk-through here) and what else I notice. For the first time in a while, I'm getting the bits at the same time as the public, so I don't have a ton of posts queued up and ready to go. I can tell you that the build number is 11.0.1440:

Microsoft SQL Server "Denali" (CTP3) - 11.0.1440.19 (X64) 
    Jun 24 2011 17:31:09 
    Copyright (c) Microsoft Corporation
    Enterprise Evaluation Edition (64-bit) on Windows NT 6.1 <X64> (Build 7601: Service Pack 1)

Operating System Support & Prerequisites

I talked about Microsoft's plans in this area several weeks ago, and wasn't surprised when I saw the list of supported operating systems in the release notes for CTP3. Here are the different sets of operating systems that are supported (or not supported), and what else you need to know to get Denali up and running on them.

 
Windows 7 & Windows Server 2008 R2 
  <blockquote>Denali is officially supported on Windows 7 Service Pack 1 and Windows Server 2008 R2 Service Pack 1. It will install and run fine if you don't have Service Pack 1 installed, but you will probably get one of those nasty-gram "known compatibility issues" dialogs that suggest you update your operating system. Nip that in the bud now, and install SP1. If you don't already have <a href="http://www.microsoft.com/download/en/details.aspx?id=22" title="http://www.microsoft.com/download/en/details.aspx?id=22" target="_blank" rel="noopener noreferrer">.NET Framework 3.5 SP1</a> installed, you will need to install it. You will need to enable both the .NET Framework 3.5 SP1 and .NET Framework 4.0 (which should already be installed) in order to install most of the common Denali components on Windows 7 and Windows Server 2008 R2. You can get away with keeping them disabled for a couple of components, but I would suggest just making sure they're enabled regardless of how much or how little you plan to install.

Windows Server 2008 R2 Server Core

Denali is supported on Windows Server 2008 R2 SP1 Server Core. This is the first time SQL Server has been officially supported on a Server Core operating system. There were hacks around that would allow you to install SQL Server 2008, for example, on Windows Server 2008 Server Core, but this configuration is *not* supported. (And if you're not aware of the benefits of Server Core, I strongly recommend you take a peek.) Note that the setup UI is not supported; you need to use Quiet (/Q) or Quiet Simple (/QS) from the command line, as well as an /Action parameter, in order to continue. If you are installing the Express version of Denali on server core, you will need to download and install the standalone installer of .NET Framework 4.0 for Server Core before proceeding with Denali setup. Unlike the "full" version of Windows Server 2008 R2, and unlike Denali setup when run against those other operating systems, the framework isn't present by default on Server Core – and the Express version of Denali will not install it for you. I'm hoping there is a clear and easy way for folks distributing Express-based applications to both normal and Server Core installations, without a whole lot of extra hassle for their users.

If you're going to install on Server Core, I highly recommend this post from Microsoft's Sethu Srinivasan:

http://sethusrinivasan.wordpress.com/2011/07/12/sql-server-denali-ctp3-on-windows-2008-r2-server-core/
 

Windows Vista & Windows Server 2008

Denali is supported on Windows Vista Service Pack 2 and Windows Server 2008 Service Pack 2. I suspect installation may be blocked if you are at Service Pack 1 or RTM (though it may just be a warning like above), so please make sure you are at Service Pack 2 if possible. Unlike previous versions of SQL Server, you will need to install the .NET Framework 3.5 SP1 and then this update from KB #956250 before you run setup. Denali will, however, install the .NET Framework 4.0, if you don't already have it. Note that CTP3 (because of PowerShell 2.0 requirements) cannot be installed on Vista & Windows Server 2008 for these operating system languages: Bulgarian, Estonian, Croatian, Lithuanian, Latvian, Romanian, Serbian, Slovak, Slovenian, Thai, or Ukrainian. In these cases setup won't be blocked per se, but you will get an error message that simply says, "This package is not applicable."

Windows XP & Windows Server 2003

Denali is *not* supported on Windows XP (or Windows Server 2003). If this is your preferred operating system, or if you have legacy applications that won't work on newer operating systems, you will need to use virtualization software (Virtual PC 2007, VirtualBox, VMWare Workstation) to run a more modern operating system, and install Denali there. You also might consider upgrading to a newer version of Windows, running Denali there, and running your legacy apps under XP mode. In Windows 7, you can run the newer version of Virtual PC, with or without XP Mode. In fact it is probably wise to consider one of these approaches regardless of what operating system you're running – it is a beta, after all.

Windows ME, 98SE, 98 & 95

Ha ha, just kidding.

 
All Operating Systems
  <blockquote>If you're not already running PowerShell 2.0, you will need it for both the database engine and Management Studio. Unlike previous versions, setup will not install PowerShell for you. Everything you need to be sure PowerShell 2.0 is enabled on your machine can be found in <a href="http://support.microsoft.com/kb/968929" title="http://support.microsoft.com/kb/968929" target="_blank" rel="noopener noreferrer">KB #968929</a>. If your operating system is x64, make sure to choose the 64-bit Management Tools and 64-bit Windows PowerShell Extensions for SQL Server. The 32-bit extensions will not work.

Time Bomb

The CTP is furnished in Express and Evaluation Editions. While the Express Edition does not expire, it is likely against the CTP EULA to run it beyond the 180 days. If you want the full product, be aware that it is a hard stop at 180 days – the product will stop working the next time you restart the service or reboot your computer. Unlike Windows, there is no secret command-line switch to re-arm the evaluation time bomb as you approach the 180 day limit. I wrote about this issue regarding CTP1 in April, and had a ton of fun trying to uninstall SQL Server 2008 R2 Evaluation Edition last October. So, just something to keep in mind.
 

Other issues you are likely to encounter

(I'm going to leave out potential issues with Analysis Services, Reporting Services, Data Quality Services, Master Data Services, and several less common issues. For full details on these things, please see the release notes when they come out.)

If you are running IPv6 only, the Help Viewer will not run correctly. The simplest workaround is to enable IPv4; there is a much more tedious workaround listed in the official release notes..

Saving a maintenance plan in Denali's designer will make it so that earlier versions of SSMS will not be able to edit it (or perhaps even open it). No word on whether the plan will still run on the previous version – I assume so since it is a breaking change in the designer, not the code it produces.

Because not all of the Visual Studio-related components are complete, after installing CTP3 on a system that is running Visual Studio 2010, you'll need to (re-)apply Visual Studio 2010 Service Pack 1.

Double-clicking on .SQL files will open a new instance of Management Studio, every time. If you want to open multiple .SQL files in the same instance of SSMS, use File > Open. IIRC this symptom was present in CTP1 as well.

In order to debug queries, you need to use the "Run as Administrator" option when launching Management Studio. This was also true in CTP1.

To take advantage of all of the features of AlwaysOn Availability Groups, in addition to this set of requirements, you'll need to be running under trace flag 9532. This is because not all of the features are finished in CTP3; it reminds me somewhat of how database mirroring was not quite ready in the initial release of SQL Server 2005, not really being supported until Service Pack 1.