Cannot open this item. You cannot use SharePoint. Your system administrator has turned off the feature.

So you are using Windows SharePoint Services 3.0 (WSS) or Microsoft Office SharePoint Server 2007 (MOSS) and you get the following message:

Cannot open this item. You cannot use SharePoint. Your system administrator has turned off the feature.

Before I get to how to fix it, here are some of the ways you may encounter this message:

• Any Task list | Actions toolbar item | Connect to Outlook
• Receive an alert (from task, list, calendar, file, etc) in Outlook and try to open it.

What does this message mean, you ask? First, let me say that it doesn't necessary mean that your administrator has turned off the feature. For example, if you are trying to open an alert / notification sent from SharePoint notifying you that a list, task, file, etc has changed and you get this message it could be a bug with Exchange. Here is the link that describes the issue.

http://support.microsoft.com/default.aspx/kb/930807/en-us

On the other hand, it could very well be exactly what the message says. To tell if this functionality truly been disabled by your administrator as the message indicates, the easiest thing is to check the registry.

To check the registry, do the following:

1. Start menu | Run... | regedit.exe
2. Navigate to HKEY_CURRENT_USER\Software\Policies\Microsoft\Office\12.0\Outlook\Options\WSS\Disable
3. If the value for Disabled is 1 then the feature is indeed disabled by your administrator. If the value is 0 then it is not disabled and I would consider it to be a bug. If you don't have 12.0 in the path above then you likely don't have Outlook 2007 and are using another version of Outlook. In that case check out the following blog
   
   http://blogs.technet.com/josebda/archive/2007/01/27/enabling-and-disabling-sharepoint-integration-in-outlook-2007.aspx.
   
   Though from what I can tell the path for Outlook 2007 is incorrect. You can always try what I specified above and the one that is noted in that blog.

You can directly edit the registry and this will work for a while. Please note, you will likely need to restart Outlook 2007 for the change to take affect. The problem is that if you are in a larger organization or one that uses Group Policies to manage such things your changes will be overwritten the next time the Group Policies are applied to your computer. You may need to contact your adminstrator to determine why they disabled this functionality in the first place and ask if they can change the policy. Good luck ;)