With a surname like O’Neill I’m used to breaking systems that need me to enter my name. Apostrophes are used in SQL commands and many programming languages to enclose string or character literals – as such, the appearance of one when not expected can mark the end of a string before the programmer of the system actually intended, leading to faults and security bugs such as SQL injection attacks.

I can’t, for example, use Asda online shopping because attempting to pay with a debit or credit card using my surname results in the site throwing a wobbler on account of the apostrophe – it claims it to be an ‘invalid character’. Small business owners’ websites will frequently bail out in a way suggesting an attack vector when I have to enter my name – they’ll see a premature end-of-string and try to parse Neill as a SQL command. Even Twitter’s not immune – view my Twitter feed and you’ll see the HTML entity code for an apostrophe in the title of the page instead of the character itself.

This week I’ve encountered three more examples that I document purely so that someone else encountering frankly weird behaviour in their systems will feel less alone:

• Office 365 doesn’t support apostrophes in your username
• If your domain login name contains an apostrophe, the Azure Storage emulator will fail to function
• If your domain login name contains an apostrophe, you’ll lose the ‘Add Service Reference’ context menu item in Visual Studio – and if you open a project that contains service references you’ll get a broken folder full of .wdsl, .disco and other files instead
  • Though at least this’ll supposedly be fixed in 2012

With Unicode ubiquitous and an assumption even down to the level of DNS that the world is small enough for internationalisation to be a fundamental component of an application, how on earth can a lonely apostrophe cause such havoc?