Error 428 Precondition Required – Causes and Fixes Contents CausesFixesStep 1: Submit Request Again Causes The header for precondition is missing, so the server could not process. Fixes Step 1: Submit Request Again Please try submitting the request again with the header -> If-Match Updated on June 25, 2020 Was this article helpful? Yes No Related Articles Error 425 Too Early – Causes and Fixes Error 424 Failed Dependency -Causes and Fixes Error 423 Locked – Causes and Fixes 218 This Is Fine – Unofficial Codes 103 Checkpoint – Unofficial Codes 404 Not Found – Causes and Fixes