Quick answer

Attributes in XML must have a name, an equals sign, and a value in single or double quotes.

XML Invalid Attribute

Attributes in XML must have a name, an equals sign, and a value in single or double quotes. Invalid syntax or unclosed quotes cause parser errors.

Common causes

How to fix

Examples

Bad

<el a=unquoted>

Good

<el a="value">

FAQ

Can an XML attribute value contain a quote?
Use the other quote for the value (e.g. attr="value with 'inside'" or attr='value with "inside"').
Are XML attribute names case-sensitive?
Yes. Attribute names are case-sensitive.

Fix it now

Try in validator (prefill this example)

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