Hi there,
Please recreate the preferences of Captivate 6.
Location for 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
You will have to close the Captivate 6 first and then rename the Captivate 6 folder to Captivate 6_OLD.
Then relaunch the captivate and check whether that fixes this issue.
Thanks.