### Please describe the problem.

`git annex get --from=myremote' show "transfer already in progress, or unable to take transfer lock".

**Likely Problem discovered!** I copied the whole remote repo (was residing on a Linux machine accessed via SMB) and pasted it into my Mac. The problem was resolved. It is likely something to do with the fact that Mac OS filesystem is **case-insensitive**. I discovered this issue when I tried to copy that remote repo with ``cp`` rather than ``tar``ing it first.


### What steps will reproduce the problem?

Remote is on a Linux machine.
Do `git annex get' on a Mac OS.
Do the same on another Linux machine.

The git annex client on the Linux machine works.
Mac OS doesn't.

rsync version for all machines: 3.1.1

### What version of git-annex are you using? On what operating system?

git-annex 5.20151019

Lubuntu 15.10.
Mac OS X 10.11.1 (El Capitan)


### Please provide any additional information below.

[[!format sh """
# If you can, paste a complete transcript of the problem occurring here.
# If the problem is with the git-annex assistant, paste in .git/annex/daemon.log


# End of transcript or log.
"""]]

### Have you had any luck using git-annex before? (Sometimes we get tired of reading bug reports all day and a lil' positive end note does wonders)

Yes.

It's wonderful. This should be a problem with Mac OS.

> [[done]]; this appears to be the same bug as 
> [[parallel_get_can_fail_some_downloads_and_require_re-getting_]], 
> which was fixed in 6.20170520.
> --[[Joey]] 
