### Please describe the problem.

On Windows, a 10GB file of mine is successfully indexed (``git annex add``'ed), but ``git annex sync --content`` always fails with rsync, saying "recvkey: received key with wrong size". This is the largest file I've tested so far, and the only one that's failed.

### What steps will reproduce the problem?

1. Copy a 10GB file to a working copy (mine is ''PNG_Sequence.rar'', 10 361 629 980 bytes).
2. Run ``git annex add``
3. Run ``git annex sync --content``

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

Windows 7 x64 with:

    git-annex version: 5.20141128-g70f997e
    build flags: Assistant Webapp Webapp-secure Pairing Testsuite S3 WebDAV DNS Feed
    s Quvi TDFA CryptoHash
    key/value backends: SHA256E SHA1E SHA512E SHA224E SHA384E SKEIN256E SKEIN512E SH
    A256 SHA1 SHA512 SHA224 SHA384 SKEIN256 SKEIN512 WORM URL
    remote types: git gcrypt S3 bup directory rsync web webdav tahoe glacier ddar ho
    ok external

### 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

commit  (Recording state in git...)
ok
pull origin
ok
copy Art/PlanetPioneers/PNG_Sequence.rar copy Art/PlanetPioneers/PNG_Sequence.ra
r (checking origin...) (to origin...)
  recvkey: received key with wrong size; discarding

sent 39 bytes  received 12 bytes  102.00 bytes/sec
rsync error: syntax or usage error (code 1) at /home/lapo/package/rsync-3.0.9-1/
src/rsync-3.0.9/main.c(1052) [sender=3.0.9]total size is 10361629980  speedup is
 203169215.29
  rsync failed -- run git annex again to resume file transfer
failed
pull origin
ok
push origin
Counting objects: 24, done.
Delta compression using up to 8 threads.
Compressing objects: 100% (11/11), done.
Writing objects: 100% (13/13), 1.06 KiB | 0 bytes/s, done.
Total 13 (delta 7), reused 0 (delta 0)
To ssh://gitannex@serv-gitannex:/home/gitannex/git-annex-test.git
   f8f70de..41bec92  git-annex -> synced/git-annex
   090ca15..e9e842b  annex/direct/master -> synced/master
ok
git-annex: sync: 1 failed

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

> [[fixed|done]] --[[Joey]]
