"This page can't be displayed"

I have seen the following error page appear "This page can't be displayed" ever so often. This has happened when I am in the Admin section adding products, and when I go to my store. This does not always happen, and appears to happen at random. What could be causing this, and how can I diagnose this issue. I have not seen any issues in the raw logs, nor are there are errors reported in the Log folder.

Thanks in advance

Please go to the root directory and click the folder called Logs and report back with the latest error ...

No errors files in the folder. I am wondering if the issue is connecting to the database, and something is happening at that point that causes it to fail [a time-out or something]