Google PageRank values are not being displayed - I'm seeing n/a/n/a instead. Why?

If your LinkMachine installation is displaying Alexa ranks correctly but is not showing Google PageRank values, it may be that Google has blocked the series of IP addresses that includes your site's address from accessing its PageRank data. This could be due to previous frequent queries of PageRank data from a script running on your site or on another site hosted using the same IP address block (most likely hosted on the same web server or at the same hosting company).

To verify this, you can download a zip file containing several utility scripts here. Unzip the file and upload the script named pagerank_test.php to your web site. Run the script from a browser and enter a URL into the form, then click Submit. If Google returns a 401 Forbidden error message, this means that your site's IP address is being blocked by Google from accessing PageRank information.

To fix this, you can ask your web host's tech support to change your site's IP address. If they are unwilling or unable to change the site's IP address to an address which is not blocked by Google, the only solution would be to transfer the site to a different host.