Title: 500 Internal Server Error when CSS an JS codes optimization enabled Last modified: May 30, 2024 --- # 500 Internal Server Error when CSS an JS codes optimization enabled * Resolved [oleksandrmelnychenko](https://wordpress.org/support/users/oleksandrmelnychenko/) * (@oleksandrmelnychenko) * [2 years ago](https://wordpress.org/support/topic/500-internal-server-error-when-css-an-js-codes-optimization-enabled/) * Hi! We updated our WP version to the latest one (6.5.3). After that, we encountered various glitches throughout our website (the navigational menu wasn’t working, fonts changed, links weren’t active, etc.). We tested it internally and discovered that those issues were related to the Autoptimize plugin settings. In particular, they appeared when we switched on CSS and JS code optimization. In these cases, the following errors (500 Internal Server Error) appear in the DevTools console: * ```wp-block-code curl 'https://104.197.4.9/wp-content/cache/autoptimize/js/autoptimize_single_4eca121cfb354e9b8cbf358773b23a09.js' \ -H 'Accept: /' \ -H 'Accept-Language: en-GB,en-US;q=0.9,en;q=0.8' \ -H 'Authorization: Basic Y3N1c2VyOmF2MTAx' \ -H 'Connection: keep-alive' \ -H 'Cookie: cs_custom_cookie=https%3A%2F%2F104.197.4.9%2F; gcl_au=1.1.1602272903.1716981448; ga=GA1.1.1380220482.1716981448; gid=GA1.1.434397399.1716981451; gat_UA-69354283-2=1; _ga_CJSE8BGE9N=GS1.1.1716981448.1.1.1716981639.25.0.0' \ -H 'Referer: https://104.197.4.9/' \ -H 'Sec-Fetch-Dest: script' \ -H 'Sec-Fetch-Mode: no-cors' \ -H 'Sec-Fetch-Site: same-origin' \ -H 'User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/125.0.0.0 Safari/537.36' \ -H 'sec-ch-ua: "Google Chrome";v="125", "Chromium";v="125", "Not.A/Brand";v="24"' \ -H 'sec-ch-ua-mobile: ?0' \ -H 'sec-ch-ua-platform: "macOS"' \ --insecure ``` * ```wp-block-code curl 'https://104.197.4.9/wp-content/cache/autoptimize/js/autoptimize_single_272f14f5de9caca54765bb008b7e660d.js?ver=1.20.2' \ -H 'Accept: /' \ -H 'Accept-Language: en-GB,en-US;q=0.9,en;q=0.8' \ -H 'Authorization: Basic Y3N1c2VyOmF2MTAx' \ -H 'Connection: keep-alive' \ -H 'Cookie: cs_custom_cookie=https%3A%2F%2F104.197.4.9%2F; gcl_au=1.1.1602272903.1716981448; ga=GA1.1.1380220482.1716981448; gid=GA1.1.434397399.1716981451; gat_UA-69354283-2=1; _ga_CJSE8BGE9N=GS1.1.1716981448.1.1.1716981639.25.0.0' \ -H 'Referer: https://104.197.4.9/' \ -H 'Sec-Fetch-Dest: script' \ -H 'Sec-Fetch-Mode: no-cors' \ -H 'Sec-Fetch-Site: same-origin' \ -H 'User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/125.0.0.0 Safari/537.36' \ -H 'sec-ch-ua: "Google Chrome";v="125", "Chromium";v="125", "Not.A/Brand";v="24"' \ -H 'sec-ch-ua-mobile: ?0' \ -H 'sec-ch-ua-platform: "macOS"' \ --insecure ``` * ```wp-block-code curl 'https://104.197.4.9/wp-content/cache/autoptimize/js/autoptimize_single_36c15f24fef18553ed968d875b2c78fb.js?ver=7.2.5' \ -H 'Accept: /' \ -H 'Accept-Language: en-GB,en-US;q=0.9,en;q=0.8' \ -H 'Authorization: Basic Y3N1c2VyOmF2MTAx' \ -H 'Connection: keep-alive' \ -H 'Cookie: cs_custom_cookie=https%3A%2F%2F104.197.4.9%2F; gcl_au=1.1.1602272903.1716981448; ga=GA1.1.1380220482.1716981448; gid=GA1.1.434397399.1716981451; gat_UA-69354283-2=1; _ga_CJSE8BGE9N=GS1.1.1716981448.1.1.1716981639.25.0.0' \ -H 'Referer: https://104.197.4.9/' \ -H 'Sec-Fetch-Dest: script' \ -H 'Sec-Fetch-Mode: no-cors' \ -H 'Sec-Fetch-Site: same-origin' \ -H 'User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/125.0.0.0 Safari/537.36' \ -H 'sec-ch-ua: "Google Chrome";v="125", "Chromium";v="125", "Not.A/Brand";v="24"' \ -H 'sec-ch-ua-mobile: ?0' \ -H 'sec-ch-ua-platform: "macOS"' \ --insecure ``` * ```wp-block-code curl 'https://104.197.4.9/wp-content/cache/autoptimize/css/autoptimize_236677754db43128def81812a1808b49.css' \ -H 'Accept: text/css,*/*;q=0.1' \ -H 'Accept-Language: en-GB,en-US;q=0.9,en;q=0.8' \ -H 'Authorization: Basic Y3N1c2VyOmF2MTAx' \ -H 'Connection: keep-alive' \ -H 'Cookie: cs_custom_cookie=https%3A%2F%2F104.197.4.9%2F; gcl_au=1.1.1602272903.1716981448; ga=GA1.1.1380220482.1716981448; gid=GA1.1.434397399.1716981451; ga_CJSE8BGE9N=GS1.1.1716981448.1.1.1716982302.60.0.0' \ -H 'Referer: https://104.197.4.9/' \ -H 'Sec-Fetch-Dest: style' \ -H 'Sec-Fetch-Mode: no-cors' \ -H 'Sec-Fetch-Site: same-origin' \ -H 'User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/125.0.0.0 Safari/537.36' \ -H 'sec-ch-ua: "Google Chrome";v="125", "Chromium";v="125", "Not.A/Brand";v="24"' \ -H 'sec-ch-ua-mobile: ?0' \ -H 'sec-ch-ua-platform: "macOS"' \ --insecure ``` * ```wp-block-code curl 'https://104.197.4.9/wp-content/cache/autoptimize/js/autoptimize_single_9a6fabd29071260dc73033a62ca73c7d.js?ver=6.2.5' \ -H 'Accept: /' \ -H 'Accept-Language: en-GB,en-US;q=0.9,en;q=0.8' \ -H 'Authorization: Basic Y3N1c2VyOmF2MTAx' \ -H 'Connection: keep-alive' \ -H 'Cookie: cs_custom_cookie=https%3A%2F%2F104.197.4.9%2F; gcl_au=1.1.1602272903.1716981448; ga=GA1.1.1380220482.1716981448; gid=GA1.1.434397399.1716981451; gat_UA-69354283-2=1; _ga_CJSE8BGE9N=GS1.1.1716981448.1.1.1716981639.25.0.0' \ -H 'Referer: https://104.197.4.9/' \ -H 'Sec-Fetch-Dest: script' \ -H 'Sec-Fetch-Mode: no-cors' \ -H 'Sec-Fetch-Site: same-origin' \ -H 'User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/125.0.0.0 Safari/537.36' \ -H 'sec-ch-ua: "Google Chrome";v="125", "Chromium";v="125", "Not.A/Brand";v="24"' \ -H 'sec-ch-ua-mobile: ?0' \ -H 'sec-ch-ua-platform: "macOS"' \ --insecure ``` * What are your recommendations? What can cause those issues? * Currently, we tested all of the above in our dev website. * Best regards, * Alex Viewing 1 replies (of 1 total) * Plugin Author [Optimizing Matters](https://wordpress.org/support/users/optimizingmatters/) * (@optimizingmatters) * [2 years ago](https://wordpress.org/support/topic/500-internal-server-error-when-css-an-js-codes-optimization-enabled/#post-17791669) * [I answered here](https://wordpress.org/support/topic/500-internal-server-error-when-css-an-js-codes-optimization-enabled-2/#post-17791480) Alex 🙂 * will close this one to avoid confusion. Viewing 1 replies (of 1 total) The topic ‘500 Internal Server Error when CSS an JS codes optimization enabled’ is closed to new replies. * ![](https://ps.w.org/autoptimize/assets/icon-256X256.png?rev=2211608) * [Autoptimize](https://wordpress.org/plugins/autoptimize/) * [Frequently Asked Questions](https://wordpress.org/plugins/autoptimize/#faq) * [Support Threads](https://wordpress.org/support/plugin/autoptimize/) * [Active Topics](https://wordpress.org/support/plugin/autoptimize/active/) * [Unresolved Topics](https://wordpress.org/support/plugin/autoptimize/unresolved/) * [Reviews](https://wordpress.org/support/plugin/autoptimize/reviews/) * 1 reply * 2 participants * Last reply from: [Optimizing Matters](https://wordpress.org/support/users/optimizingmatters/) * Last activity: [2 years ago](https://wordpress.org/support/topic/500-internal-server-error-when-css-an-js-codes-optimization-enabled/#post-17791669) * Status: resolved