After you install MS12-030 (Vulnerabilities in Microsoft Excel could allow remote code execution - http://support.microsoft.com/kb/2663830) you may see the following error message appear when trying to do sorts in your spreadsheet: “Excel cannot complete this task with available resources. Choose less data or close other applications.”
Updated - 6/28/2012 - a fix for this problem is now in the June Cumulative update located here - http://support.microsoft.com/kb/2712235 and fixes the problem described here - http://support.microsoft.com/kb/2687317.
This problem happens when you highlight the entire spreadsheet by clicking the upper left button to select all cells (circled in red below).
When you select all of the cells using this button and then perform a custom sort, the error message appears on 32-bit versions of Excel. On 64-bit versions of Excel, the sort won't produce an error, but it will take a longer time than expected to perform the sort operation.
Note: If you have installed the update you will want to remove the registry key. Having the update and the regkey will still exhibit the behavior.
UPDATE 4/19/2013: This is just one of the reasons that you may get this error message. There has been a new KB article that addresses many other cases for the error see the following KB for more information.
2779852 How to Troubleshooting Available Resources errors in Excel