ArcToolbox tools will not open, prompts to open/save files - Windows 7 (fix)

Discussion created by curtvprice Champion on Jul 29, 2011
Latest reply on Oct 26, 2011 by sarahereed
I felt this was worth reposting this in its own thread here as we have seen this too.

Up until yesterday everything was fine. I have no idea what setting changed, but I am getting the same window when I try to use any tool - "Navigation to the webpage was canceled" and then a "File Download" window pops up prompting me to open or save a file titled "MdDlgContent.htm" and MdDlgHelp.htm". I click cancel, but the tools just close and repeat the same thing when I try to open again.

I am using ArcGIS 9.3.1 and can open all of my files just fine, add layers, but just can't use the Toolbox

This fix is documented in KB article 38564:
Problem: Opening a geoprocessing tool from ArcToolbox prompts to open or save file