docker: Error response from daemon: invalid volume specification: "C:\data URIs/data URIsrw"

TL;DR: Format the Windows path the way docker expects: forward slashes and lowercase drive, like -v c:/data URIs/data, or quote the path. Backslashes and unquoted drive letters break the volume parser. On Docker Desktop for Windows, -v C:\data URIs/data fails while -v c:/data URIs/data works.

The error

docker: Error response from daemon: invalid volume specification: 'C:\data URIs/data URIsrw': invalid volume specification.

Fix it

1. Rewrite the bind with forward slashes:

docker run -v c:/data URIs/data [image] Expected: container starts.

1. In PowerShell, quote to stop the shell mangling the path:

docker run -v "c:/data URIs/data" [image] Expected: works.

1. From Git Bash/MSYS, use the posix-style path or double slashes:

docker run -v //c/data URIs/data [image] Expected: works.

When this applies

• Docker Desktop on Windows with -v or --mount bind paths
• CI on windows-latest runners

When this does NOT apply

• Linux hosts (bind paths are native there)
• "includes invalid characters for a local volume name" (named volume rule, separate skill)

Versions

Docker Desktop 4.x on Windows.

Why it happens

The volume spec parser splits on : and treats backslashes as escapes. C:\data parses into something the validator rejects, while c:/data splits cleanly into source and destination.

Edge cases

• File sharing must be enabled for the drive in Docker Desktop Settings > Resources > File Sharing, or the bind silently shows an empty dir.
• WSL2 backend: prefer paths inside the WSL distro ([HOME]/...) over /mnt/c; they are much faster.
• --mount type=bind,source=c:/data,target=/data is stricter but gives clearer errors than -v.