Since there is no longer any shortcut to start Internet Explorer 9 without addons, in safe mode on Windows 7, here is how to achieve that :
The first, and quick method would be to simply type the following command into the search bar located at the bottom of the start menu :
iexplore -extoff
The second method is more likely to make it permanent and add it directly to the shortcut itself.
1. Right click on the Internet Explorer shortcut and then click on Properties.
2. Locate the Target field and add -extoff flag at the end of the IE executable path with a space after the quote ” :
"C:\Program Files (x86)\Internet Explorer\iexplore.exe" -extoff
3. Now IE will always start in safe mode if started from this shortcut. You can now go into the parameters and disable the add-on you want if it was making Internet Explorer fail to start.