Troubleshooting
Search for error messages or symptoms to find solutions
Frequently Occurring Issues
CORS Error
Common"has been blocked by CORS policy" error when calling backend API
SPA 404 Error
Common404 Not Found appears when refreshing the page
Environment Variable Issue
process.env or import.meta.env is undefined
Auth Cookie Issue
Login works but cookies are not saved
Build Failure
npm run build or docker build fails
DNS NXDOMAIN
CommonDNS_PROBE_FINISHED_NXDOMAIN appears when opening your domain
SSL Certificate Error
CommonERR_CERT_COMMON_NAME_INVALID and HTTPS certificate warning
Failed to fetch
TypeError: Failed to fetch in browser
Node Version Mismatch
Build fails because local and CI Node versions differ
429 Rate Limit
HTTP 429 Too Many Requests due to API throttling
Mixed Content Block
CommonHTTPS page is blocked from loading HTTP resources
502/504 Gateway Timeout
Proxy-to-backend latency causes 502/504 timeout errors
Build OOM
CI build fails with heap out of memory
CORS Preflight 405
OPTIONS preflight request fails with 405
Webhook Signature Failure
Webhook signature verification fails in integrations
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