Hi there,
Please close captivate first, and rename the preferences folder,
Location for the captivate preferences folder is:
Windows 7: C:\Users\[user name]\AppData (hidden folder)\Local\Adobe\Adobe Captivate 6 folder
Windows XP: C:\Documents and Settings\[user name]\Local Settings\Application Data\Adobe\Adobe Captivate 6 folder
Mac: /Users/[user name]/Library/Preferences/Adobe Captivate 6 folder
Rename the Captivate 6 Folder to Captivate 6_OLD.
Then Launch the captivate.
Thanks.