As all bloggers know, permalinks are the permanent universal resource identifiers used as addresses for blog posts. One post, one permalink. The permalink doesn’t change so that people can link and refer to it over time and it can easily be found.
Well, I guess I’ve commited permalink sacrilege because I changed the settings of my permalinks from the default in WordPress to one with the name of the post attached to the domain name (e.g. jarche.com/permalink-woes/). Unfortunately that created a whole bunch of routing errors, on top of the redirects from previous Drupal (my last content management system) permalinks such as – jarche.com/node/123. I am now back to the default permalink style for WordPress (jarche.com/?p=123) and will not change it again.
I also discovered that all older links were renamed as well, so that what should be jarche.com/?p=123 was for a short period renamed jarche.com/OLD123 , and that style of naming no longer works.
My apologies to anyone who has unsuccessfully tried to follow an old permalink. My stats show that there are many of these each day. All that I can suggest is that you search, in the search box on the top right, for the title or some keyword. Sorry :-(

