How To Disable DotNetNuke Tasks in the Database
If your site is not accessible it is possible your DotNetNuke scheduled tasks are hung and need to be disabled directly through your DNN Database. To disable these tasks follow the steps below.
These steps require you to have Microsoft SQL Server Management Studio installed on your computer. Microsoft SQL Server Management Studio Express 2008 is available for free from Microsoft, and can be downloaded at http://www.microsoft.com/download/en/details.aspx?id=22985
Always back up the website before making any changes to the database . Shared hosting customers can do this through the Control Panel. Refer to Back Up Your Website Using Plesk. Dedicated server customers can back up the site either through the Control Panel, or through the Control Suite. Refer to How to Back Up a Domain Using Control Suite.