Note: the above code is a trimmed down version, hence the error message showing slightly different code.

Hi Max,

Have you tried with just 'MM' ? :-) You may have an M too many there.

Edit: Also, I think you should be able to skip the apostrophes around @createDate :-)

Hey, thanks for the reply. I have tried that, even tried 'yyyy'. I also saw the apostrophe's after posting this message but I cannot edit the post but just left it. Removing them dosnt fix it either. 

<xsl:value-of select="umbraco.library:FormatDateTime(@createDate, 'yyyy')" />

MMMM is valid - http://en.wikibooks.org/wiki/Umbraco/Reference/umbraco.library/FormatDateTime

Any other ideas?

Another attempt:

<?xml version="1.0" encoding="utf-8" ?>
<!DOCTYPE xsl:stylesheet [
        <!ENTITY nbsp "&#x0A;">
]>
<xsl:stylesheet
        version="1.0"
        xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
        xmlns:umb="urn:umbraco.library"
        exclude-result-prefixes="umb"
>

        <xsl:output method="xml" indent="yes" omit-xml-declaration="yes" />

        <xsl:param name="currentPage" />
        <xsl:variable name="level" select="1" />
        
        <xsl:variable name="navRoot" select="$currentPage/ancestor-or-self::*[@level = $level][not(umbracoNaviHide = 1)]" />
        <xsl:variable name="navRootItems" select="$navRoot/*[@isDoc][not(umbracoNaviHide = 1)]" />

        <xsl:template match="/">
          <div class="navtree">
            <table cellspacing="0">
              <tr>
                <td id="navleft" />
                <td id="navcentre">
                  <ul>
                    <li>
                      <xsl:if test="$currentPage/@nodeName = 'Home'"><xsl:attribute name="class">current</xsl:attribute></xsl:if>
                      <a href="/">Home</a>
                    </li>
                  </ul>

                  <xsl:if test="$navRootItems">
                    <ul id="treemenu1">
                      <xsl:apply-templates select="$navRootItems" />
                    </ul>
                  </xsl:if>
                </td>
                <td id="navright" />
              </tr>
            </table>
          </div>
        </xsl:template>

        <xsl:template match="*[@isDoc]">
          <li>
            <xsl:if test="@id = $currentPage/@id"><xsl:attribute name="class">current</xsl:attribute></xsl:if>
            <a href="{umb:NiceUrl(@id)}">
              <xsl:choose>
                <xsl:when test="@level = 4 and (self::uBlogsyFolderMonth | self::umbracoBlogDateFolder | self::DateFolder)">
                 <xsl:call-template name="niceDate">
                   <xsl:with-param name="date" select="@createDate" />
                  </xsl:call-template>
                </xsl:when>
                <xsl:otherwise> 
                  <xsl:apply-templates select="@nodeName" />
                </xsl:otherwise>
              </xsl:choose>
            </a>
            <xsl:if test="*[@isDoc][not(umbracoNaviHide = 1)][not((self::uBlogsyFolderMonth | self::umbracoBlogDateFolder | self::DateFolder)[@level = 5])]">
              <ul>
                <xsl:apply-templates select="*[@isDoc][not(umbracoNaviHide = 1)][not((self::uBlogsyFolderMonth | self::umbracoBlogDateFolder | self::DateFolder)[@level = 5])]" />
              </ul>
            </xsl:if>
          </li>
        </xsl:template>
        
        <xsl:template match="@nodeName[string-length() &gt; 25]">
          <xsl:attribute name="title">
            <xsl:value-of select="." />
          </xsl:attribute>
          <xsl:value-of select="concat(substring(., 1, 24), '&#8230;')" />
        </xsl:template>
  
        <xsl:template name="niceDate">
          <xsl:param name="date" />
          <xsl:value-of select="umbraco.library:FormatDateTime($date, 'MMMM')" />
        </xsl:template>
        
</xsl:stylesheet>

Same error.. this has REALLY stumped me. Even when I use

<xsl:value-of select="Exslt.ExsltDatesAndTimes:formatdate($date, 'd')"/>

in the above it does the same thing. Even when I paste the whole code into the live version of the website in a new unused xslt file it does not save. even when I hard code the date and put it right at the top of the xslt file next to the html it fails. :/

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