Title: [If Modified Since HTTP Header] Support | WordPress.org

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# [If Modified Since HTTP Header] Support

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 *  -  [HELP! Not working…](https://wordpress.org/support/topic/help-not-working-4/)
    -  Started by: [tomthomsen](https://wordpress.org/support/users/tomthomsen/)
    - 2
    - 2
    -  [10 years, 11 months ago](https://wordpress.org/support/topic/help-not-working-4/#post-6093734)
    -  [iSaumya](https://wordpress.org/support/users/isaumya/)
 *  -  [The plugin returns Header "Last-Modified: Thu, 01 Jan 1970 00:00:00 GMT"](https://wordpress.org/support/topic/the-plugin-returns-header-last-modified-thu-01-jan-1970-000000-gmt/)
    -  Started by: [kanenas](https://wordpress.org/support/users/kanenas/)
    - 2
    - 7
    -  [10 years, 11 months ago](https://wordpress.org/support/topic/the-plugin-returns-header-last-modified-thu-01-jan-1970-000000-gmt/#post-6013628)
    -  [kanenas](https://wordpress.org/support/users/kanenas/)
 *  -  [not for Litespeed server](https://wordpress.org/support/topic/not-for-litespeed-server/)
    -  Started by: [stathis_k91](https://wordpress.org/support/users/stathis_k91/)
    - 2
    - 2
    -  [10 years, 11 months ago](https://wordpress.org/support/topic/not-for-litespeed-server/#post-5916995)
    -  [iSaumya](https://wordpress.org/support/users/isaumya/)
 *  -  [Recheck returned a 400 Bad request](https://wordpress.org/support/topic/recheck-returned-a-400-bad-request/)
    -  Started by: [goodimp](https://wordpress.org/support/users/goodimp/)
    - 2
    - 2
    -  [10 years, 11 months ago](https://wordpress.org/support/topic/recheck-returned-a-400-bad-request/#post-5907609)
    -  [iSaumya](https://wordpress.org/support/users/isaumya/)
 *  -  [Your Plugin Not Working](https://wordpress.org/support/topic/your-plugin-not-working/)
    -  Started by: [creativemind1](https://wordpress.org/support/users/creativemind1/)
    - 2
    - 1
    -  [10 years, 11 months ago](https://wordpress.org/support/topic/your-plugin-not-working/#post-5872790)
    -  [iSaumya](https://wordpress.org/support/users/isaumya/)
 *   

 * ![](https://s.w.org/plugins/geopattern-icon/if-modified-since-header_f8f8f8.svg)
 * [If Modified Since HTTP Header](https://wordpress.org/plugins/if-modified-since-header/)
 * [Frequently Asked Questions](https://wordpress.org/plugins/if-modified-since-header/#faq)
 * [Support Threads](https://wordpress.org/support/plugin/if-modified-since-header/)
 * [Active Topics](https://wordpress.org/support/plugin/if-modified-since-header/active/)
 * [Unresolved Topics](https://wordpress.org/support/plugin/if-modified-since-header/unresolved/)
 * [Reviews](https://wordpress.org/support/plugin/if-modified-since-header/reviews/)