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Cloudflare 521 Error After Update: Fixes That Work - Fix HTTP 429 Too Many Requests in Command Prompt-Windows Defender Performance: Disable Real-Time Protection

2026-06-14 04:40:08
Cloudflare 521 Error After Update: Fixes That Work - Fix HTTP 429 Too Many Requests in Command Prompt-Windows Defender Performance: Disable Real-Time Protection

Result check

  • Keep one change per test run so you know which step helped.
  • Undo temporary changes after the issue is confirmed.