The issue may be related to the initial activation after installing in on the machine without internet access. One thing that you should try however is to delete the cache file to see if it has an effect on the error you are getting. If it does not then you may need to have a license file generated for you if the issue is associated with the activation. Here is a link to a thread that discusses clearing out the cache, please give this a try and let us know what the result is:
showthread.php?t=1589