[{"data":1,"prerenderedAt":419},["ShallowReactive",2],{"\u002Fblog\u002Fnextjs-web-build-errors-fixes-2026\u002F":3,"\u002Fblog\u002Fnextjs-web-build-errors-fixes-2026\u002F-related":389,"\u002Fblog\u002Fnextjs-web-build-errors-fixes-2026\u002F-resources":398},{"id":4,"title":5,"author":6,"body":10,"canonical":326,"category":327,"checker":326,"createdAt":328,"description":329,"disclosure":330,"extension":331,"faq":332,"heroActions":345,"howTo":326,"lastVerified":326,"location":350,"meta":351,"navigation":357,"ogImage":326,"path":358,"primaryKeyword":359,"readingTime":360,"related":326,"seo":361,"seoTitle":326,"sources":362,"stem":379,"tags":380,"takeaways":381,"updatedAt":328,"url":387,"__hash__":388},"blog\u002Fblog\u002Fnextjs-web-build-errors-fixes-2026.md","Next.js and Web Build Errors: 8 Fixes (2026)",{"name":7,"social":8},"Simon Dziak",{"twitter":9},"@SzymonDziak",{"type":11,"value":12,"toc":305},"minimark",[13,30,36,41,44,49,73,77,100,104,107,111,123,127,145,149,166,170,173,177,198,202,218,222,235,239,242,272,283,287],[14,15,16,20,21,25,26,29],"p",{},[17,18,19],"strong",{},"Short answer:"," web app errors split into build failures, where ",[22,23,24],"code",{},"next build"," or ",[22,27,28],{},"npm run build"," stops, and runtime errors, where the deployed site breaks in the browser or on the server. Find your error below; each one links to a full fix page checked against the Next.js, Vite, Node.js or Netlify documentation.",[14,31,32,35],{},[17,33,34],{},"Next.js and web build errors are easiest to fix once you know whether the build, the browser or the server threw them."," The 8 errors below stop web apps from building or working after deploy, including apps generated by AI builders. Facts about each tool come from its own documentation, as checked on the linked fix page; the advice on what to do and in which order is App369’s.",[37,38,40],"h2",{"id":39},"nextjs-errors-when-a-page-renders","Next.js errors when a page renders",[14,42,43],{},"These two errors appear when a page renders, in the browser console or the server log. Each names what didn’t match: the HTML, or the image host.",[45,46,48],"h3",{"id":47},"hydration-error-the-server-html-didnt-match","Hydration error: the server HTML didn’t match",[14,50,51,52,55,56,59,60,67,68,72],{},"Something renders differently on the server and in the browser: a read of ",[22,53,54],{},"window",", ",[22,57,58],{},"localStorage"," or the time during render, invalid HTML nesting, or a browser extension. On iPhone, according to the ",[61,62,66],"a",{"href":63,"rel":64},"https:\u002F\u002Fnextjs.org\u002Fdocs\u002Fmessages\u002Freact-hydration-error",[65],"nofollow","Next.js hydration docs",", “iOS attempts to detect phone numbers, email addresses, and other data in text content and convert them into links, leading to hydration mismatches.” Full steps: ",[61,69,71],{"href":70},"\u002Ffix\u002Fnextjs-hydration-error\u002F","Next.js hydration error",".",[45,74,76],{"id":75},"image-error-the-hostname-isnt-configured","Image error: the hostname isn’t configured",[14,78,79,80,83,84,89,90,95,96,72],{},"The image comes from a host that isn’t in ",[22,81,82],{},"images.remotePatterns",". The ",[61,85,88],{"href":86,"rel":87},"https:\u002F\u002Fnextjs.org\u002Fdocs\u002Fmessages\u002Fnext-image-unconfigured-host",[65],"Next.js docs"," say “Hostname: example.org is different from ",[61,91,94],{"href":92,"rel":93},"http:\u002F\u002Fwww.example.org",[65],"www.example.org"," and from subdomains like assets.example.org”, so list each host exactly, with its protocol, port and path. Full steps: ",[61,97,99],{"href":98},"\u002Ffix\u002Fnextjs-image-unconfigured-host\u002F","Next.js image unconfigured host",[37,101,103],{"id":102},"nextjs-errors-on-the-server-or-at-build-time","Next.js errors on the server or at build time",[14,105,106],{},"These three come from how a page reads request data or receives uploads. The error message names the function involved.",[45,108,110],{"id":109},"usesearchparams-should-be-wrapped-in-a-suspense-boundary","“useSearchParams() should be wrapped in a suspense boundary”",[14,112,113,114,118,119,72],{},"The ",[61,115,88],{"href":116,"rel":117},"https:\u002F\u002Fnextjs.org\u002Fdocs\u002Fmessages\u002Fmissing-suspense-with-csr-bailout",[65]," say “Reading search parameters through useSearchParams() without a Suspense boundary will opt the entire page into client-side rendering.” Wrap the smallest component that reads it in Suspense, or keep the page a Server Component. Full steps: ",[61,120,122],{"href":121},"\u002Ffix\u002Fnextjs-usesearchparams-suspense-boundary\u002F","useSearchParams Suspense boundary",[45,124,126],{"id":125},"dynamicservererror-dynamic-server-usage","“DynamicServerError: Dynamic Server Usage”",[14,128,129,25,132,135,136,140,141,72],{},[22,130,131],{},"cookies()",[22,133,134],{},"headers()"," ran outside the render it belongs to: inside a timer, or in a promise nobody awaited. The ",[61,137,88],{"href":138,"rel":139},"https:\u002F\u002Fnextjs.org\u002Fdocs\u002Fmessages\u002Fdynamic-server-error",[65]," describe the timer case as “The function was called inside of a setTimeout or setInterval, causing the value to be read outside of the call stack that the context was bound to.” Read the values first and await every helper that uses them. Full steps: ",[61,142,144],{"href":143},"\u002Ffix\u002Fnextjs-dynamic-server-usage-error\u002F","Next.js Dynamic Server Usage",[45,146,148],{"id":147},"server-action-fails-on-uploads-over-1-mb","Server Action fails on uploads over 1 MB",[14,150,151,152,157,158,161,162,72],{},"According to the ",[61,153,156],{"href":154,"rel":155},"https:\u002F\u002Fnextjs.org\u002Fdocs\u002Fapp\u002Fapi-reference\u002Fconfig\u002Fnext-config-js\u002FserverActions",[65],"Next.js serverActions docs",", “By default, the maximum size of the request body sent to a Server Action is 1MB.” Raise ",[22,159,160],{},"bodySizeLimit"," with room to spare. On Vercel, files over 4.5 MB should go from the browser straight to storage. Full steps: ",[61,163,165],{"href":164},"\u002Ffix\u002Fnextjs-server-action-body-size-limit\u002F","Next.js Server Action body size limit",[37,167,169],{"id":168},"vite-nodejs-and-netlify","Vite, Node.js and Netlify",[14,171,172],{},"These three errors appear in Vite apps, Node.js builds and Netlify Functions. Each is a mismatch between the app and where it runs.",[45,174,176],{"id":175},"vite-failed-to-load-module-script-mime-type-texthtml","Vite: “Failed to load module script” (MIME type text\u002Fhtml)",[14,178,179,180,185,186,189,190,193,194,72],{},"The browser asked for a JavaScript file and got an HTML page. After a deploy, according to ",[61,181,184],{"href":182,"rel":183},"https:\u002F\u002Fvite.dev\u002Fguide\u002Fbuild",[65],"Vite’s build docs",", “the hosting service may delete the assets from previous deployments,” so old HTML asks for files that are gone. Check the catch-all rewrite to ",[22,187,188],{},"index.html"," and the ",[22,191,192],{},"base"," setting too. Full steps: ",[61,195,197],{"href":196},"\u002Ffix\u002Fvite-failed-to-load-module-script-mime-type\u002F","Vite failed to load module script",[45,199,201],{"id":200},"nodejs-err_ossl_evp_unsupported","Node.js “ERR_OSSL_EVP_UNSUPPORTED”",[14,203,113,204,209,210,213,214,72],{},[61,205,208],{"href":206,"rel":207},"https:\u002F\u002Fnodejs.org\u002Fen\u002Fblog\u002Frelease\u002Fv17.0.0",[65],"Node.js 17 release notes"," say “it’s likely that your application or a module you’re using is attempting to use an algorithm or key size which is no longer allowed by default with OpenSSL 3.0.” Upgrade the build tooling; ",[22,211,212],{},"--openssl-legacy-provider"," is a temporary workaround. Full steps: ",[61,215,217],{"href":216},"\u002Ffix\u002Fnode-err-ossl-evp-unsupported\u002F","Node.js ERR_OSSL_EVP_UNSUPPORTED",[45,219,221],{"id":220},"netlify-function-times-out","Netlify Function times out",[14,223,224,225,230,231,72],{},"Netlify lists a 60-second limit for synchronous functions and doesn’t mark it as configurable. Time out each outside call, move the function’s region near the database on a Pro or Enterprise plan, or run long work as a background function, which per ",[61,226,229],{"href":227,"rel":228},"https:\u002F\u002Fdocs.netlify.com\u002Fbuild\u002Ffunctions\u002Fbackground-functions\u002F",[65],"Netlify’s docs"," returns “an initial 202 success response” straight away. Full steps: ",[61,232,234],{"href":233},"\u002Ffix\u002Fnetlify-function-timeout\u002F","Netlify Function timeout",[37,236,238],{"id":237},"which-to-check-first","Which to check first",[14,240,241],{},"The fastest route is the first error in the build log or the browser console, with the file and line it names. App369’s full order for a web app that just broke:",[243,244,245,254,257,260,269],"ol",{},[246,247,248,249,25,251,253],"li",{},"Note where it fails: ",[22,250,24],{},[22,252,28],{},", the browser console, or a server or function log.",[246,255,256],{},"Run the production build locally, where a build error is faster to read and fix.",[246,258,259],{},"For a browser error, test in a private window with extensions off.",[246,261,262,263,55,265,268],{},"For a server error, find the function the message names (",[22,264,131],{},[22,266,267],{},"useSearchParams()",", a Server Action) and read how it is called.",[246,270,271],{},"Check what changed since the last good deploy: packages, Node.js version, config.",[14,273,113,274,278,279,72],{},[61,275,277],{"href":276},"\u002Ffix\u002Fvercel\u002F","Vercel and Next.js errors page"," lists every fix for both. For deploy and function errors on Vercel, see the ",[61,280,282],{"href":281},"\u002Fblog\u002Fvercel-errors-deploy-function-fixes-2026\u002F","Vercel errors guide",[37,284,286],{"id":285},"need-a-hand","Need a hand?",[14,288,289,290,294,295,299,300,304],{},"App369 fixes single web build and runtime bugs at a fixed price. If one bug is the whole problem, the ",[61,291,293],{"href":292},"\u002Ffixed-price\u002Fflutter-firebase-bug-fix\u002F","App Fix Ticket"," covers it in two fixed-price steps: a $450 diagnosis that finds the root cause and gives you a fixed quote for the fix, then the fix itself. If the app was built with an AI builder and more is going on, the ",[61,296,298],{"href":297},"\u002Ffixed-price\u002Fai-app-rescue\u002F","AI-Built App Rescue"," starts with a Launch Check of the whole app. Or ",[61,301,303],{"href":302},"\u002Fcontact\u002F","describe the problem"," and get a written quote.",{"title":306,"searchDepth":307,"depth":307,"links":308},"",2,[309,314,319,324,325],{"id":39,"depth":307,"text":40,"children":310},[311,313],{"id":47,"depth":312,"text":48},3,{"id":75,"depth":312,"text":76},{"id":102,"depth":307,"text":103,"children":315},[316,317,318],{"id":109,"depth":312,"text":110},{"id":125,"depth":312,"text":126},{"id":147,"depth":312,"text":148},{"id":168,"depth":307,"text":169,"children":320},[321,322,323],{"id":175,"depth":312,"text":176},{"id":200,"depth":312,"text":201},{"id":220,"depth":312,"text":221},{"id":237,"depth":307,"text":238},{"id":285,"depth":307,"text":286},null,"AI & Technology","2026-11-02T12:00:00.000Z","Next.js hydration error, useSearchParams build failure or a Vite app that breaks after deploy? 8 web build and runtime errors, and how to fix each one.","App369 publishes this guide and sells a fixed-price App Fix Ticket for single bugs like these.","md",[333,336,339,342],{"question":334,"answer":335},"How do I fix a Next.js hydration error?","Make the server and the first browser render produce the same HTML. Move reads of window, localStorage or the current time into useEffect, fix invalid nesting such as a div inside a p, and test in a private window to rule out browser extensions.",{"question":337,"answer":338},"Why does next build fail with useSearchParams() should be wrapped in a suspense boundary?","A component reads the query string without a Suspense boundary around it, which would push the whole page to client-side rendering. Wrap that component in Suspense, or keep the page a Server Component and move the useSearchParams code into a child Client Component.",{"question":340,"answer":341},"Why do Next.js images from my storage bucket fail?","The image host isn't in images.remotePatterns, or the pattern doesn't match exactly. Each part of the address is matched strictly, so www, subdomains, the protocol, the port and the path all have to be covered.",{"question":343,"answer":344},"Can App369 fix a Next.js or build error for me?","Yes. The App Fix Ticket covers one reproducible bug in two fixed-price steps: a $450 diagnosis that finds the root cause and gives you a fixed quote for the fix, then the fix itself.",[346,348],{"label":347,"to":276},"All Vercel and Next.js fixes",{"label":349,"to":292},"Start with a $450 diagnosis","Miami, FL",{"readingTimeStats":352},{"text":353,"minutes":354,"time":355,"words":356},"5 min read",4.345,260700,869,true,"\u002Fblog\u002Fnextjs-web-build-errors-fixes-2026","nextjs errors","6 min",{"title":5,"description":329},[363,365,367,369,371,373,375,377],{"title":364,"url":63},"Next.js docs, Text content does not match server-rendered HTML",{"title":366,"url":116},"Next.js docs, Missing Suspense boundary with useSearchParams",{"title":368,"url":138},"Next.js docs, DynamicServerError",{"title":370,"url":86},"Next.js docs, next\u002Fimage Un-configured Host",{"title":372,"url":154},"Next.js docs, serverActions",{"title":374,"url":182},"Vite docs, Building for production",{"title":376,"url":206},"Node.js 17.0.0 release notes",{"title":378,"url":227},"Netlify docs, Background Functions","blog\u002Fnextjs-web-build-errors-fixes-2026","nextjs errors, nextjs hydration error, usesearchparams suspense boundary, dynamic server usage, next image unconfigured host, server action body size limit, vite failed to load module script, err_ossl_evp_unsupported",[382,383,384,385,386],"A hydration error means the server HTML and the first browser render differ. Read browser-only values such as window or the time after mount, not during render.","Reading useSearchParams() without a Suspense boundary opts the whole page into client-side rendering, so wrap the smallest part that needs it.","Server Actions accept a 1 MB request body by default. On Vercel, raising the limit doesn't lift the 4.5 MB function cap.","A Vite \"Failed to load module script\" error after a deploy can come from old HTML asking for files the new deploy removed.","ERR_OSSL_EVP_UNSUPPORTED comes from OpenSSL 3.0 blocking an old algorithm. The legacy provider flag is a temporary workaround, not the fix.","https:\u002F\u002Fapp369.com\u002Fblog\u002Fnextjs-web-build-errors-fixes-2026\u002F","QNTRPmpHX0J7NaeVBWGSPu-dOPbbqHZM458uLk-u8o0",[390,394],{"path":391,"title":392,"description":393,"category":327},"\u002Fblog\u002Fai-api-errors-openai-claude-gemini-mcp-fixes-2026","AI API Errors: 7 OpenAI, Claude, Gemini and MCP Fixes (2026)","AI feature broken by a 401, 429 or 529, or an MCP connector that won't connect? 7 OpenAI, Anthropic, Gemini and MCP errors, what each means and how to fix it.",{"path":395,"title":396,"description":397,"category":327},"\u002Fblog\u002Fapp-store-google-play-rejections-fixes-2026","App Store and Google Play Rejections: 13 Fixes (2026)","App rejected by Apple or Google Play? 13 rejections, from Guidelines 2.1, 4.3 and 5.1.1 to Play's Data safety form and 12-tester rule, and how to fix each.",[399,401,405,409,413,416],{"keyword":5,"url":387,"title":5,"relevance":400},64,{"keyword":402,"url":403,"title":402,"relevance":404},"Flutter iOS Build Failed After an Upgrade? Fix CocoaPods and Xcode Errors (2026)","https:\u002F\u002Fapp369.com\u002Fblog\u002Fflutter-ios-build-failed-after-upgrade-2026\u002F",17,{"keyword":406,"url":407,"title":406,"relevance":408},"Vercel Errors: 9 Deploy and Function Fixes (2026)","https:\u002F\u002Fapp369.com\u002Fblog\u002Fvercel-errors-deploy-function-fixes-2026\u002F",15,{"keyword":410,"url":411,"title":410,"relevance":412},"Expo and Flutter Build Errors: 12 Fixes (2026)","https:\u002F\u002Fapp369.com\u002Fblog\u002Fexpo-flutter-build-errors-fixes-2026\u002F",13,{"keyword":392,"url":414,"title":392,"relevance":415},"https:\u002F\u002Fapp369.com\u002Fblog\u002Fai-api-errors-openai-claude-gemini-mcp-fixes-2026\u002F",10,{"keyword":417,"url":418,"title":417,"relevance":415},"Firebase Auth Errors: 9 Sign-In Fixes (2026)","https:\u002F\u002Fapp369.com\u002Fblog\u002Ffirebase-auth-errors-sign-in-fixes-2026\u002F",1793632895443]