Hello! Let's troubleshoot your PDF download issue in Odoo 17.4.

  First, clear your browser cache and cookies in Firefox. This often resolves display issues after an upgrade.

  Next, try accessing the PDF using a different browser (e.g., Chrome or Edge) to see if the issue is specific to Firefox on Windows 7.

  Check your Odoo logs for any error messages related to PDF generation or rendering. These logs can provide clues about the root cause. You can typically find these in the Odoo configuration file or via the Odoo web interface if properly configured.

  Ensure that the wkhtmltopdf library, which Odoo uses to generate PDFs, is correctly installed and configured. It may need to be reinstalled or updated after the upgrade, although Windows 7 is not officially supported by wkhtmltopdf.

  If the issue persists, there may be a compatibility problem with Windows 7. Consider upgrading to a more recent operating system, as Windows 7 is no longer supported and may cause unexpected behavior.

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https://www.pragtech.co.in/contact-us-mql.html

Hi,

The white screen appears because Odoo 17.4 uses modern PDF rendering not supported by Windows 7.

Older Firefox versions can’t handle the new PDF viewer correctly.

Try updating Firefox to ESR 115, the last version compatible with Windows 7.

If possible, use a newer browser like Chrome or Edge on Windows 10 or 11.

You can also download the PDF directly instead of previewing it in the browser.

This issue is not with Odoo itself but due to outdated system and browser compatibility.

Hope it helps.