This article applies to Camtasia Studio 7.1.1 or later.
This problem can occur because during the uninstall we prompt the user if they want to keep or delete their library. To circumvent this issue use the following property in the command line.
Below is an example on how to use this property.
msiexec.exe /x Setup_CS7_EVALUATION_ENU.msi TSC_KEEP_LIBRARY=1