This category contains 5 posts

Fix ERR_NETWORK_CHANGED on Inspiron 17

My Dell Inspiron 17 laptop starting giving regular ERR_NETWORK_CHANGED errors when I switched from ADSL2+ via Exetel to NBN via iiNet. Note that this error only occurs when using a LAN cable to directly connect the laptop to the gateway. The error doesn’t happen if connected via Wi-Fi. It seems that the issue is due to … Continue reading

Fix “[Error 5] Access is denied” when upgrading pip on windows

When using pip to install a python package from a Windows command window, pip displayed the following message You are using pip version 7.0.1, however version 8.1.2 is available. You should consider upgrading via the ‘pip install –upgrade pip’ command. However, when I ran that command, pip displayed the following error WindowsError: [Error 5] Access … Continue reading

A thoughtful analysis of the NTSB report of the SpaceShipTwo accident

This article in Flying magazine gives what I think is a very good analysis of the NTSB report of the unfortunate SpaceShipTwo accident. I agree with the author when he states The NTSB chose to find that the cause of the SpaceShipTwo crash was not the inexplicable action of the copilot, but rather the failure of engineers … to … Continue reading

Drop a letter to increase password strength

I found an interesting way to increase the strength of a password when using multiple words to create a password (as suggested by the now famous xkcd comic). Drop a letter from a common word! Note that I am NOT suggesting that using dictionary words is the best password policy [1], but if you are … Continue reading

Fixing Dell LA90PS0-00, 90W AC Adapter for Inspiron 9400 laptop

For the past year or so, my laptop has has only been running at half speed (0.96 GHz), because the AC adapter was unrecognised (even though it is a genuine Dell power supply). Sometimes, after the laptop had been running for about 2 hours, I could get the adapter recognised by unplugging and reinserting the power lead at … Continue reading