Windows: resume failures from EBADF transcript read errors are now explained

What

A session's transcript is the file where Claude Code saves a conversation so it can be resumed later. On Windows, reading it sometimes failed with an EBADF error even though the file opened normally, and resuming gave no reason why.

• Claude Code now recognises Windows errors with code EBADF from a read, including when the error is wrapped inside another error.
• When --resume fails this way, by session ID or by .jsonl file path, the old one-line error ("Unable to load transcript from file" or "Failed to resume session") now gets an explanation. It says "Windows reported an error (EBADF) when Claude Code read this session's transcript file, although the file had opened normally." It adds that security, encryption or endpoint-management software may be intercepting file reads, and suggests excluding the transcript or .claude folder, or allowing Claude Code, in that software.
• These failures are now logged as load errors rather than reported as crashes.
• /resume <id> now shows a message starting "Failed to resume: " and logs the failure when a session fails to load with a recognised error. Before, it failed with no message.

Why

Windows users whose sessions would not resume now get a likely cause and a concrete fix, usually an exclusion in their security software.