Thanks for getting in touch, sorry that you’ve run into a problem here.
By far the most common cause of this problem is Antivirus, are you able to check and confirm if you have whitelisted c:\Octopus*? Even if you can only do this is a proof of concept that would be a good place to start.
Failing that you’re going to have to try and work out which application is holding a lock on the file(s) in question. This thread has a good list of options, we should show the file that is locked in our logging outputs.
Hopefully that helps, please let me know how you get on and if you need any further assistance.