MCP servers issues on Windows
Issues the maintainers labelled both platform:windows and area:mcp.
755 issues · 128 open · 627 resolved (83%) · first seen Jun 19, 2025
Is this getting better or worse?
This class of problem is holding steady. 190 new reports in the last 90 days vs 239 in the 90 before — -21%. The open backlog peaked at 130 in 2026-09 and sits at 128 today.
Derived by counting each matching issue from its creation date until it closed. First-party
computation over the anthropics/claude-code tracker — the trend is not published
anywhere upstream.
Which builds report this
421 of these reports name the Claude Code build they were running, spanning 171 releases. Heaviest reporters:
- Claude Code v2.1.241
- Claude Code v2.1.119
- Claude Code v2.1.258
- Claude Code v2.1.195
- Claude Code v2.1.114
- Claude Code v2.1.20
- Claude Code v2.1.246
- Claude Code v2.1.232
Report volume, not a defect count: an issue can mention a build without that build having caused the failure. Versions come from the version string in the bug-report template, matched against real published tags.
Do these get fixed?
Median time to close is 32 days across 627 closures. Of the 627 closures with a recorded reason, 21% were closed as completed and 494 as not-planned or duplicate. The most recent completed fix landed in 2026-10.
Workarounds reported by the community
256 of these issues post a workaround someone says worked. The highest-engagement ones:
- Claude in Chrome extension not connecting despite being installed and enabled
- ✅ Workaround Confirmed Working (Windows 11, Claude Code 2.1.29) Root cause identified by @kimchi-developer in 21791 — the function (socket path discovery) doesn't return Windows named pipe path. Quick Fix 1. Backup cli.j…
Found in the thread of #21371 · resolved - [CRITICAL] MCP Parameter Serialization Bug in Both Claude Code and Claude Desktop
- …subsequent parameter calls fail with serialization errors. Workaround Currently requires restarting the entire Claude session after each parameter-based MCP operation, making MCP impractical for real workflows. --- Prio…
Found in the description of #4192 · resolved - [BUG] GitHub connector shows "Connected" but exposes no tools in Cowork (Windows 11, app v1.8555.2.0)
- Same issue here, also in the Claude desktop app (Cowork). GitHub shows "Connected" in Customize → Connectors, but exposes zero GitHub tools in any session — Claude reports no GitHu
Found in the thread of #61682 · still open - Critical: No way to bypass MCP tool approval prompts in VSCode extension
- …urpose of MCP servers for external API integration - Forces workarounds (writing custom scripts instead of using MCP) Comparison with CLI Question: Does the CLI version of Claude Code ( terminal command) respect the conf…
Found in the description of #10801 · resolved - [BUG] Cowork Google Drive MCP cannot see content in any Workspace Shared Drive
- Seeing the same. my workaround is to temporarily have a process that copies necessary files to a Drive folder (from the shared drive) and update my Skills to reference this until fixed
Found in the thread of #53442 · still open
Excerpts are quoted from the linked issue so you can judge relevance before opening it. Threads that only ask for a workaround, or report that there is none, are excluded. These are community suggestions, not official guidance from Anthropic — read the full thread before applying one.
Matching issues 1–100
Ranked by community engagement (reactions weighted over comments). Listing the top 300 of 755 matches; the statistics above cover all 755.
- Claude in Chrome extension not connecting despite being installed and enabled
- [CRITICAL] MCP Parameter Serialization Bug in Both Claude Code and Claude Desktop
- [BUG] GitHub connector shows "Connected" but exposes no tools in Cowork (Windows 11, app v1.8555.2.0)
- Critical: No way to bypass MCP tool approval prompts in VSCode extension
- [BUG] Cowork Google Drive MCP cannot see content in any Workspace Shared Drive
- Google Drive claude.ai connector not loading in VS Code extension despite being connected in claude.ai
- Desktop app MCP Tools hanging for 5-10 minutes then failing.
- [Regression, Windows+macOS] Cross-session messaging silently broken since CCD 2.1.224+ — messages dropped, recipient sessions wedged 15-20 min (hadFirstResponse=false); fixed in 2.1.237 for some installs, stable channel still affected
- [BUG] Claude Desktop MCP: tool call responses dropped by client after first successful round-trip (Windows, regression in CCD v2.1.22)
- [BUG] MCP file system not working
- [BUG] Claude Desktop 1.0.734: MCP servers fail to initialize - 'Cannot read properties of undefined (reading cmd)'
- Cluade Code in Windows is a pain in ***
- --dangerously-load-development-channels should support skipping the confirmation dialog
- Claude in Chrome extension not connecting on Windows despite MCP server showing "connected"
- [BUG] Claude Desktop Local mode rejects folders outside C:\Users on Windows, even with valid MCP config
- [Bug] Anthropic API Error: PNG screenshots sent with incorrect image/jpeg MIME type
- Claude-in-Chrome Windows & WSL working fixes
- [Bug] /compact fails with "Tool names must be unique" even after disabling all MCP servers (v2.0.70)
- [BUG] v1.0.98 is not reading project .mcp.json and rewriting .claude/settings.local.json
- [BUG] MCP servers requiring OAuth authentication don't expose tools - no browser auth flow triggered
- [BUG] M365 MCP OAuth fails with AADSTS9000411 - parameter 'prompt' is duplicated
- [BUG] v2.1.68 (updated 2026-03-04) opens 3 blank VS Code windows when claude is started in the integrated terminal.
- [BUG] Claude Code Web interactive sessions lost all claude.ai MCP connectors ~April 23, 2026 while routines retain them
- [Bug] Plugin marketplace discovery broken after update to v2.0.62
- Claude in Chrome Extension Not Connecting on Windows 11
- Chrome Extension: EADDRINUSE - Native Host and MCP Server both try to create pipe listener
- [BUG] Claude Desktop: extension install fully broken — "Install Extension" no-ops and drag-and-drop falls through the modal into the chat
- Windows 11: Terminal freezes on startup in 2.1.30/2.1.31 (regression from 2.1.29)
- [BUG] Local MCP server will not trust self-signed certs
- MCP OAuth tokens expire frequently, requiring manual /mcp reconnect
- [BUG] MCP server instructions from initialize response are not passed to the model
- [BUG] MCP client rejects valid tools/list response due to strict validation of ttlMs/cacheScope fields (Roblox Studio MCP server)
- [BUG] Chrome extension v1.0.40 does not connect to Claude Code CLI --chrome on Windows
- [BUG] MCP server with SSE/HTTP transport fails with OAuth discovery error — no way to disable OAuth
- [FEATURE] Make MCP Tool Execution Timeout Configurable in Claude Desktop
- [BUG] Windows: Claude Code 2.0.65 fails with ENOENT error due to colons in MCP log directory paths
- [BUG] Windows: Cowork browser automation tools missing after Claude Desktop update — computer-use tools never register
- [BUG] Claude Desktop silently hangs installing any local .mcpb with a deflated entry larger than ~16 KB
- [BUG] Tool search has broken ranking, causing Claude to fail to find a tool despite exact name match
- [BUG] Task subagents fail to inherit permissions in MCP server mode (affects both WSL and native Windows)
- Microsoft 365 MCP connector: redirect URI mismatch (AADSTS50011)
- Chrome extension native host crashes on Windows (Bun v1.3.5 panic)
- [BUG] MCP tools fail with "Browser extension is not connected" despite /chrome showing Connected
- [BUG] aude in Chrome browser extension not connecting from Claude Code on Windows despite correct configuration
- [BUG] MCP headers with environment variable substitution not being sent from .mcp.json
- [BUG] MAX100 subscription - abnormal quota consumption and rate_limit_error with multi-session Claude Code
- [BUG] Browser extension shows "Enabled/Installed" but tools report "not connected"
- [BUG] Claude Desktop (Windows): local MCP tool calls freeze while the session tab is not visible; hosted calls and scheduled tasks unaffected
- [BUG] Cowork on macOS 1.8555.2 — zero MCP tools bind in any install path (.mcpb + SDK bridge + Custom Connectors + project .mcp.json); spawn pipeline missing --mcp-config since 2026-05-23 auto-update
- Session hangs indefinitely with spinning thinking indicator — 3 confirmed variants (+ /btw MCP teardown)
- [BUG] VS Code extension: startup() handshake timed out 30000ms despite CLI working (v2.1.101 Windows)
- MCP server 'claude_design' (frontend-design plugin): 404 Streamable HTTP error
- [BUG] Claude Desktop (Windows): MCP tool calls hard-terminated and bridge wedge after repeated timeouts
- MCP scheduled-tasks no longer appear in Routines panel after 2.1.80
- Claude-in-Chrome MCP: extension executes but CLI receives 'not connected' error (Windows)
- [BUG] Windows: Atlassian Remote MCP Server fails to connect
- [BUG] Atlassian Rovo MCP widgets (e.g. Jira search results) render unreadably bright since today — worked fine until yesterday
- [BUG] send_message (cross-session) offers only "Allow once" — no persistent grant, unlike other requiresUserInteraction tools
- [BUG] MCP OAuth authorization URL wraps in terminal — Ctrl+click opens truncated link
- Claude-in-Chrome MCP tools steal window focus on every tool call
- PostToolUse hooks with additionalContext not surfacing for MCP tool calls
- [BUG] Windows: Chrome extension native host crashes with EADDRINUSE pipe conflict
- unable to enable developer MCP in Claude Desktop
- [BUG] OAuth authorization for HTTP MCP servers missing required scope parameter
- [BUG] Atlassian MCP Sign In does not work
- [BUG] Cowork (Windows): mcp__workspace__bash denied in every session after updating to 1.44121.1.0 — worked on 1.40609.1.0
- [FEATURE] Allow Claude Code VS Code extension to read MCP servers from VS Code's mcp.json
- Chrome extension not connecting to Claude Code via native messaging on Windows 11
- MCP client rejects tool calls when outputSchema declares JSON Schema draft-07 dialect
- [BUG] Custom connector tools never reach new conversations since Desktop v1.17377.1 (directory connectors fine)
- [BUG] Custom local MCP server tools disabled in Cowork and Claude Code, but work in Claude Chat Desktop app
- [BUG] Task tool subagents spawn duplicate MCP servers and leak ~/.claude/tasks/ directories on Windows
- [BUG] Dataverse MCP connector — all write operations fail with JObject does not match expected type 'String' for item parameter
- [BUG] VSCode extension doesn't load MCP servers on Windows due to drive letter case mismatch in .claude.json project key lookup
- [BUG] Chrome MCP tools never load in VS Code — claude-vscode MCP fails with -32601: Method not found (Windows 11)
- Chrome extension not connecting on Windows 11 (Build 26200)
- [BUG] Cursor IDE integration fails: option disappears after brief availability
- [BUG] Backend changes break MCP image analysis with GLM API - All Claude Code versions affected
- Local MCP servers fail with 'Not ready after 60 seconds' even though the remote connection succeeds (shared-pool readiness bug)
- [BUG] Windows: case-sensitive `.claude.json` project-key lookup silently drops MCP servers across CLI/VS Code — recurring bug, repeatedly auto-closed unfixed
- [BUG] Live Artifacts (CoworkArtifacts.callMcpTool) reject local stdio MCP servers on cold start — claude.ai relay rejects server name as non-UUID
- Microsoft 365 MCP OAuth fails - relative resource_metadata in WWW-Authenticate header
- MCP Chrome navigation: only one domain permission prompt per session
- Claude in Chrome MCP connection fails on Windows - extension running but never connects
- [BUG] Claude in Chrome MCP shows "connected" but tools return "Browser extension is not connected"
- [BUG] Cowork local sessions: all mcp__workspace__* tools denied without any prompt after SDK 2.1.258 (Windows)
- [BUG] Windows: plugin-shipped MCP servers using bare `npx` fail with `spawn ENOENT` (LSP fix from #17312 missed the MCP spawn path)
- [BUG] Custom MCP connector OAuth tokens fail to persist across restart; menu "Connect" silently fails while in-chat auth works
- [DOCS] Add warning that mcpServers in settings.json / settings.local.json is silently ignored
- [BUG] Chrome native host crashes with Bun panic on Windows 11 (v2.1.25)
- [BUG] MCP Fails on native Windows
- Gmail connector can't attach local files without sending base64 through the tool call
- MCP elicitation is answered `decline` by a controlling client that never drew a prompt (desktop app, --input-format stream-json, SDK 0.3.234)
- [BUG] Claude Code MCP OAuth aborts on server-advertised protected-resource path mismatch — IBKR connector works in Claude Chat, fails in Claude Code
- VS Code extension: streams end with sdk_stream_ended_no_result after first chunk, on one machine only
- [FEATURE] Computer Use support in Claude Code CLI on Windows
- [Windows] --dangerously-load-development-channels does not enable inbound channel notifications
- [BUG] MCP Streamable HTTP SSE reconnection regressed in 2.1.83
- --channels ignored — Discord plugin channel notifications not working (v2.1.81)
- [BUG] Chrome MCP fails with EADDRINUSE: native host tries to create new pipe server instead of connecting to existing one