org: Validating OpenDocument XML
12.9.11.5 Validating OpenDocument XML
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Occasionally, you will discover that the document created by the ODT
exporter cannot be opened by your favorite application. One of the
common reasons for this is that the ‘.odt’ file is corrupt. In such
cases, you may want to validate the document against the OpenDocument
RELAX NG Compact Syntax (RNC) schema.
For de-compressing the ‘.odt’ file(1): 
(emacs)File Archives.
For general help with validation (and schema-sensitive editing) of XML
files: (nxml-mode)Introduction.
If you have ready access to OpenDocument ‘.rnc’ files and the needed
schema-locating rules in a single folder, you can customize the variable
‘org-odt-schema-dir’ to point to that directory. The ODT exporter will
take care of updating the ‘rng-schema-locating-files’ for you.
---------- Footnotes ----------
(1) ‘.odt’ files are nothing but ‘zip’ archives
Info Catalog
org: Customizing tables in ODT export
org: Advanced topics in ODT export