[Resolved] receiving “Cannot Modify Header” error

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[charlesR-4]

I am currently getting this error in my WP dashboard (along with several depreciation notices):

Warning: Cannot modify header information - headers already sent by (output started at /home1/grabbagm/public_html/wp-content/plugins/wp-views/vendor/toolset/toolset-common/inc/autoloaded/field/group/factory.php:134) in /home1/grabbagm/public_html/wp-includes/pluggable.php on line 1435

Depending on which dashboard page I'm on it, it will also point to /home1/grabbagm/public_html/wp-admin/admin-header.php on line 9

I have tried deactivating all other plugins except Toolset and using the WordPress 2025 theme and I still get the error.

[Minesh]

Hello. Thank you for contacting the Toolset support.

Based on the information you shared it's not clear that due to what Toolset plugin its showing deprecated notice or warning.

Can you please try to switch to other theme and check or even disable Toolset plugin one by one and check what plugin is causing this deprecated notice or warning and also share what deprecated notice you see.

Maybe you can activate WP_DEBUG and share the error log.
- https://toolset.com/documentation/programmer-reference/debugging-sites-built-with-toolset/#general-toolset-debugging

[charlesR-4]

As I said, I've tested this with several themes, including the current WordPress 2025 theme. I still get this error when all plugins are deactivated except for Toolset Types and Toolset Views. The "Cannot modify header" error does not appear when only Toolset Types is active. It appears when Toolset Types AND Toolset Views are both activated. I am running the most recent version of both plugins.

This is the error log from the site under these conditions:

[02-Dec-2024 16:22:34 UTC] PHP Deprecated: ctype_digit(): Argument of type int will be interpreted as string in the future in /home1/grabbagm/public_html/wp-content/plugins/wp-views/vendor/toolset/toolset-common/inc/autoloaded/field/group/factory.php on line 134
[02-Dec-2024 16:22:34 UTC] PHP Deprecated: ctype_digit(): Argument of type int will be interpreted as string in the future in /home1/grabbagm/public_html/wp-content/plugins/wp-views/vendor/toolset/toolset-common/inc/autoloaded/field/group/factory.php on line 134
[02-Dec-2024 16:22:34 UTC] PHP Warning: Cannot modify header information - headers already sent by (output started at /home1/grabbagm/public_html/wp-content/plugins/wp-views/vendor/toolset/toolset-common/inc/autoloaded/field/group/factory.php:134) in /home1/grabbagm/public_html/wp-admin/admin-header.php on line 9
[02-Dec-2024 16:22:34 UTC] PHP Deprecated: ctype_digit(): Argument of type int will be interpreted as string in the future in /home1/grabbagm/public_html/wp-content/plugins/wp-views/vendor/toolset/toolset-common/inc/autoloaded/field/group/factory.php on line 134
[02-Dec-2024 16:23:39 UTC] PHP Deprecated: ctype_digit(): Argument of type int will be interpreted as string in the future in /home1/grabbagm/public_html/wp-content/plugins/wp-views/vendor/toolset/toolset-common/inc/autoloaded/field/group/factory.php on line 134
[02-Dec-2024 16:23:39 UTC] PHP Deprecated: ctype_digit(): Argument of type int will be interpreted as string in the future in /home1/grabbagm/public_html/wp-content/plugins/wp-views/vendor/toolset/toolset-common/inc/autoloaded/field/group/factory.php on line 134
[02-Dec-2024 16:23:39 UTC] PHP Warning: Cannot modify header information - headers already sent by (output started at /home1/grabbagm/public_html/wp-content/plugins/wp-views/vendor/toolset/toolset-common/inc/autoloaded/field/group/factory.php:134) in /home1/grabbagm/public_html/wp-admin/admin-header.php on line 9
[02-Dec-2024 16:23:39 UTC] PHP Deprecated: ctype_digit(): Argument of type int will be interpreted as string in the future in /home1/grabbagm/public_html/wp-content/plugins/wp-views/vendor/toolset/toolset-common/inc/autoloaded/field/group/factory.php on line 134

[Minesh]

Ok - we have similar report for Toolset Types plugin and its been fixed but yet to release the hotfix.

However, this belongs to Toolset Views, please allow me to check with our Devs and I will get back to you as soon as I know mroe.

However - this is notice, it will not break your site. you may opt to disable the WP_DEBUG or disable the debug display:

define('WP_DEBUG_DISPLAY', false);

[charlesR-4]

Ok, thank you. For context, this was happening on a site that is 15 years old, but regularly maintained. I also found that Toolset Types was causing interference with WP Bakery, which I've never seen happen. It was preventing pages from being able to be published. I ended up just starting over with a fresh install and am rebuilding the site from scratch. So far, I have not encountered any issues on the fresh install.