"migration" may have moved over more than it should: try a repair reinstall,
and if that does not help, Follow Autodesk's Uninstall AutoCAD instructions:
http://usa.autodesk.com/adsk/servlet/ps/dl/item?siteID=123112&id=10243968&linkID=9240617
restart your PC.
reinstall LT, skip migration.
Back up all of your customizations first.
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Dean Saadallah
http://LTisACAD.blogspot.com
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