[BUG] Cowork: Plugin marketplace fails to load when TEMP directory is on a different drive (EXDEV cross-device link error)

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

Cowork's plugin marketplace fails to load with an EXDEV (cross-device link not permitted) error when the Windows TEMP directory is located on a different physical drive than the C: drive.
The VM workspace image (rootfs.vhdx) is downloaded to the TEMP directory, then Cowork attempts to rename (move) it to C:\Users\<username>\AppData\Roaming\Claude\vm_bundles\claudevm.bundle\rootfs.vhdx. Since rename cannot operate across different filesystem boundaries on Windows, the operation fails.

What Should Happen?

The plugin marketplace should load successfully regardless of where the TEMP directory is located. The file operation should use copy + delete (or fs.copyFile + fs.unlink) instead of fs.rename when the source and destination are on different drives/volumes.
Suggested Fix
Replace the rename call with a cross-device-safe operation, for example:
javascript// Instead of:
fs.renameSync(src, dest);

// Use:
try {
fs.renameSync(src, dest);
} catch (err) {
if (err.code === 'EXDEV') {
fs.copyFileSync(src, dest);
fs.unlinkSync(src);
} else {
throw err;
}
}

Error Messages/Logs

Error Message
Failed to load marketplaces

Error invoking remote method '$eipc_message$_8da60cf1-ffca-4300-be84-6af2f603bd1c_$_claude.web_$_CustomPlugins_$_listMarketplaces': 
Error: EXDEV: cross-device link not permitted, rename 'D:\temp\wvm-MEDS6B\rootfs.vhdx' -> 
'C:\Users\leong\AppData\Roaming\Claude\vm_bundles\claudevm.bundle\rootfs.vhdx'
Steps to Reproduce

Steps to Reproduce

Configure Windows TEMP/TMP environment variables to point to a drive other than C: (e.g., D:\temp)
Open Claude Desktop on Windows 11
Switch to Cowork mode
Click to browse plugins
Plugin cards appear as blank placeholders (loading state)
After some time, the error message above appears

Claude Model

Sonnet (default)

Is this a regression?

I don't know

Last Working Version

_No response_

Claude Code Version

Claude 1.1.4498 (24f768) 2026-02-26T19:47:09.000Z

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

Non-interactive/CI environment

Additional Information

<img width="1023" height="675" alt="Image" src="https://github.com/user-attachments/assets/fb5a017b-408e-4089-96b9-74df8dc37a93" />