Dealing with 0x80600001 errors

Maybe you have just seen a message like this:

Error: uncaught exception: [Exception… “Component returned failure code: 0x80600001 [nsIXSLTProcessor.importStylesheet]”  nsresult: “0x80600001 (<unknown>)”  location: “JS frame :: file:///home/adrian/webtech/cia.html :: fulltable :: line 47”  data: no]

If you have then chances are you are working on some XSL/XSLT (the above comes from a piece of coursework I am working on which manipulates an XML representation of data from the CIA World Fact Book).

The error indicates that your XSL is broken and non-compliant and the problem is that Firefox/Mozilla is much stricter about what is broken than it is likely your command line XSLT processor is: the piece of XSL which generated the above message seemed to fly through xsltproc on my Linux box.

The best way to fix this is to take out the lines, one by one, from your XSL and look for the one that breaks the transformation. To avoid being inadvertently tied up in some issue of plagiarism later on I cannot post the XSL I was working on when this came up, but I had a line like this:

<xsl:apply-templates match="//item"/>

That is bad XSL – the match should be a select but as xsltproc happily covered up for my mistake and generated the XHTML I was looking for I could not understand why Firefox was flagging the error on this line of Javascript xsltproc.importStylesheet(xmlxsl).

It also took me a while to find an online explanation, so I wrote this.