We have discovered that spyware or adware can cause ActiveX controls, such as the editor, to no longer function properly. In particular, we have seen pop up blockers and the Alexa toolbar crash the editor.
It is recommended that you scan your system for spyware. If you use the latest version of McAfee VirusScan, it should detect and remove those files. You can download Spy Sweeper, which gives you a free scan to remove spyware/adware.