Please consult these relevant items from the FAQ:

• A3. I get a "licencing subsystem fatal error" during installation
   
• A4. I've just received my registration key, where do I type it?
   
• A5. I have logged on as administrator but xplorer² won't accept my registration key
   
• A6. I want to try xplorer² but it asks for a registration key when I start it
   
• A7. xplorer² stopped working before the 21st day of the trial
   

If you have questions about the payment process including invoices, please consult the payments FAQ

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