Resolving a Down for Maintenance (Err2) Error
After performing an update, a Down for Maintenance (Err 2) error may occur when visiting WHMCS pages:
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Causes
This message is displayed whilst the update process is in progress. If an update is not currently being applied, it indicates a version mismatch between the PHP files and the MySQL database.
Some possible causes for this error include:
- The auto-updater was terminated before it could complete
- A new version of PHP files have been uploaded but the update process has not yet been performed
- A patch set was manually applied to an incompatible version of the software
Resolution
Follow these steps to complete the update process:
1. Visit the install sub-directory within your WHMCS directory. For example www.yoursite.com/whmcs/install
2. A screen like this will be displayed:
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If a 404 Page Not Found error is displayed instead, refer to the Performing a Manual Update documentation and follow all steps for a Full Release Version
3. Agree to the End User License Agreement
4. Click the Continue button at the bottom of the next screen:
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5. Make a backup of the WHMCS MySQL database, then click Start the Upgrade:
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6. The database update process will now commence:
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7. Within a few minutes, a success message should be displayed:
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If an Upgrade Failed message is displayed instead, refer to the Updating WHMCS Troubleshooting section for assistance
8. Delete the install sub-directory from your server.
9. Click the link to return to the admin area.
10. Ensure that the Version Number displayed on the Admin Dashboard sidebar or in Help > System Health Status is the version you were updating to:
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The update process is now complete and you can continue using WHMCS, enjoying the new features and stability improvements of the latest update!
We recommend reviewing the Release Notes