While Microsoft Chief Executive Officer, Steve Ballmer, denied the possibility of a free and open source Windows operating system, for both the client and the server side, the fact of the matter is that the company does support Windows Vista, Vista Service Pack 1 and Windows Server 2008 free rides. Essentially, all three versions of the Windows operating system support installation without entering product keys. And even deployment process of Windows XP SP3 was changed to replicate that of Windows Vista. In this context, Microsoft introduced, as far as Vista and Windows Server 2008 is concerned, an evaluation period referred to as either Initial Grace or Activation Grace.

During the evaluation period users are able to run either Vista, with or without SP1, and Windows Server 2008 and test drive the platforms without purchasing the product, activating it or entering a product key. When it comes down to Vista and Vista SP1 the Home Basic, Home Premium, Business and Ultimate editions of the operating system can be evaluated for a total of 30 days. After the initial month, users have to enter a product key, or prolong the operating system's Initial Grace period. In Vista (+SP1) this can be done via the "slmgr" command.

All that users have to do is open a command prompt window with elevated privileges and type "slmgr" without the inverted comas, in order to get a full list of options available with this command. The Windows Software Licensing Management Tool offers the possibility of entering product keys, activating the operating system, but also to reset the licensing status of the machine. This is possible via the "slmgr -rearm" command. This can be entered for a total of three times, prolonging the evaluation period of Vista up to 120 days.

And Microsoft has revealed that the same is possible with Windows Server 2008. "Evaluating Windows Server 2008 software does not require product activation. Any edition of Windows Server 2008 may be installed without activation, and it may be evaluated for 60 days. Additionally, the 60-day evaluation period may be reset (re-armed) three times. This action extends the original 60-day evaluation period by up to 180 days for a total possible evaluation time of 240 days. Although you can reset the 60-day evaluation period, you cannot extend it beyond 60 days at any time. When you reset the current 60-day evaluation period, you lose whatever time is left on the previous 60-day evaluation period. Therefore, to maximize the total evaluation time, wait until close to the end of the current 60-day evaluation period before you reset the evaluation period," Microsoft stated.

Just like Windows Vista, Windows Server 2008 features the Windows Software Licensing Management Tool. Installed without a product key, Windows Server 2008 offers a default activation grace period of 60 days. In an elevated command prompt window enter "slmgr.vbs -dli" in order to display the number of days the server platform still has until the end of the 60-day evaluation period. In order to prolong the activation period, all you have to do is enter "slmgr.vbs –rearm" and hit Enter. After you restart Windows Server 2008, you will find that the re-arm command has prolonged the activation grace period by another 60 days. In this manner, you will be able to use Windows Server 2008 for a total of 240 days.

Microsoft also revealed that there is a way to automate the extension of Windows Server 2008's evaluation period:

"You may want to set up a process that automatically resets the evaluation period every 60 days. One way to automate this process is by using the Task Scheduler. You can configure the Task Scheduler to run the Slmgr.vbs script and to restart the server at a particular time. To do this, follow these steps:
1. Click Start, point to Administrative Tools, and then click Task Scheduler.
2. Copy the following sample task to the server, and then save it as an .xml file. For example, you can save the file as Extend.xml.
3. In the sample task, change the value of the following "UserID" tag to contain your domain and your alias:
domainalias
4. In the Task Scheduler, click Import Task on the Action menu.
5. Click the sample task .xml file. For example, click Extend.xml.
6. Click Import.
7. Click the Triggers tab.
8. Click the One Time trigger, and then click Edit.
9. Change the start date of the task to a date just before the end of your current evaluation period.
10. Click OK, and then exit the Task Scheduler.