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Please note that while your maintenance plan is active, you are entitled to use every minor and major version of the licensed product. You should be able to use your license key in the latest version of our products without any problems. You can also upgrade it to version 7 from the main page of your http://www.tracker-software.com
The context menu in Windows Explorer is enabled by our shell extensions. Please try to re-register our shell extensions using the instructions from the following knowledge base article and let us know if this solves the problem:https://www.tracker-software.com/knowledgebase/395