SAXParseException — XML Parsing Error in Solr Configuration Files

The Error

You reload your Opensolr Index (or upload new config files) and it fails with one of these errors:

org.apache.solr.common.SolrException: Unable to reload core [your_core]
Caused by: Error loading solr config from .../solrconfig.xml
Caused by: org.xml.sax.SAXParseException; lineNumber: 18; columnNumber: 13;
Open quote is expected for attribute "name" associated with an element type "array".

Or:

ERROR XmlConfigFile:168 - Exception during parsing file: solrconfig.xml
org.xml.sax.SAXParseException: Open quote is expected for attribute "name"

Or similar errors mentioning:

• SAXParseException
• Open quote is expected
• element type is not closed
• The element type must be terminated
• Content is not allowed in prolog
• Unexpected end of file
• Exception during parsing file

All of these mean the same thing: your XML configuration file has a syntax error, and Solr cannot parse it.

What Is Actually Happening

Solr's configuration files (solrconfig.xml, schema.xml, search.xml, and all extras) are XML files. XML has very strict syntax rules — much stricter than HTML. A single missing quote, an unclosed tag, or a stray character will cause the entire file to be rejected.

When Solr tries to reload your index, it reads these XML files through a parser called SAX (Simple API for XML). If the parser hits invalid syntax, it throws a SAXParseException and the reload fails. Your index stays on the old configuration — nothing is broken, but the new config is not applied.

How to Read the Error Message

The SAXParseException error gives you everything you need to find the problem:

org.xml.sax.SAXParseException;
  systemId: solrres:/search.xml;    ← THE FILE with the error
  lineNumber: 18;                   ← THE LINE number
  columnNumber: 13;                 ← THE COLUMN on that line
  Open quote is expected for        ← WHAT is wrong
  attribute "name" associated
  with an element type "array".

In this example:

• The error is in search.xml (not solrconfig.xml — but referenced by it)
• On line 18, column 13
• The attribute name is missing its opening quote

Common Errors and Fixes

Missing or Wrong Quotes

The most common error. XML requires double quotes around attribute values.

<!-- WRONG — missing quotes -->
<str name=myfield>value</str>
<arr name=components>

<!-- CORRECT — double quotes required -->
<str name="myfield">value</str>
<arr name="components">

Also watch for smart quotes (curly quotes) pasted from word processors or web pages:

<!-- WRONG — smart/curly quotes (look similar but are different characters!) -->
<str name=\xe2\x80\x9cmyfield\xe2\x80\x9d>value</str>

<!-- CORRECT — straight double quotes -->
<str name="myfield">value</str>

Unclosed or Mismatched Tags

Every opening tag must have a matching closing tag with the exact same name.

<!-- WRONG — unclosed tag -->
<str name="dir">${solr.ulog.dir:}

<!-- WRONG — mismatched tags -->
<str name="dir">${solr.ulog.dir:}</int>

<!-- CORRECT -->
<str name="dir">${solr.ulog.dir:}</str>

Unescaped Special Characters

XML has five characters that must be escaped when used inside values:

<!-- WRONG — unescaped ampersand -->
<str name="q">rock & roll</str>

<!-- CORRECT — escaped ampersand -->
<str name="q">rock &amp; roll</str>

Files Referenced by solrconfig.xml

The error might point to a file like search.xml, elevate.xml, or solrconfig_extra.xml. These are included by solrconfig.xml via <xi:include> directives. The syntax error is in that referenced file, not in solrconfig.xml itself.

Check the systemId in the error message to find the right file:

• solrres:/search.xml → edit search.xml
• solrres:/schema.xml → edit schema.xml
• solrres:/solrconfig_extra.xml → edit solrconfig_extra.xml

How to Fix It

Step 1: Identify the File and Line

Read the error message. It tells you the file name, line number, and column number.

Step 2: Open the File in the Config Editor

Go to your Opensolr Index Control Panel → Config Files Editor → select the file mentioned in the error.

Step 3: Go to the Exact Line

Navigate to the line number mentioned in the error. Look for:

• Missing or extra quotes
• Unclosed tags
• Unescaped &, <, or > characters
• Tags that open as one name and close as another

Step 4: Fix and Save

Correct the XML syntax error. Save the file.

Step 5: Reload

Click Reload in your Opensolr control panel. If the reload succeeds, the fix worked. If it fails again, read the new error message — there may be another syntax error on a different line.

How to Validate XML Before Uploading

Before uploading config files to Opensolr, validate them locally:

Using xmllint (Linux/Mac):

xmllint --noout solrconfig.xml
# No output = valid XML
# Error output = shows line and column of the problem

Online validators: Search for "XML validator online" — paste your XML and it will highlight syntax errors instantly.

Quick Checklist

• Read the error message — it tells you the file, line, and problem
• Check for missing quotes around attribute values (most common cause)
• Check for unclosed tags — every <tag> needs a </tag>
• Check for unescaped characters — & must be &, < must be <
• Watch for smart quotes from copy-paste — replace with straight " quotes
• If the error points to search.xml or *_extra.xml, edit that file, not solrconfig.xml
• Use xmllint to validate XML locally before uploading
• Reload after fixing — if it succeeds, you are good

Having trouble finding the XML error? Reach out to us at support@opensolr.com with the error message — we will pinpoint and fix it for you.