OK, went further down.
- Installation on a brand new win7 computers works.
- I double-checked the win10 computer and the c:\users\agouai~1\appdata\local\temp\tmpv6xdvi\.cipd\pkgs\5zs6D0TNxz\368312758\x folder exists. It seems that folders therein are created "ReadOnly". Changing ths manually does not work since a new folder tmpxxxxxx is created at each attempt.

Adding components for further triage by the Chrome infra team. 

Can't reproduce :(

I will contact you separately to provide access to the machine.

For comparison, here's how first gclient run looks on my Windows 10 machine:

C:\Users\Vadim\Downloads\depot_tools>gclient
Installing python 2.7.6...
Fetching from https://storage.googleapis.com/chrome-infra/python276_bin.zip
Ensuring CIPD client is up-to-date
GET https://chrome-infra-packages.appspot.com/_ah/api/repo/v1/instance/resolve?version=bccdb9a605037e3dd2a8a64e79e08f691a6f159d&package_name=infra%2Ftools%2Fcipd%2Fwindows-amd64
CIPD client bccdb9a605037e3dd2a8a64e79e08f691a6f159d => bccdb9a605037e3dd2a8a64e79e08f691a6f159d
GET https://chrome-infra-packages.appspot.com/_ah/api/repo/v1/client?instance_id=bccdb9a605037e3dd2a8a64e79e08f691a6f159d&package_name=infra%2Ftools%2Fcipd%2Fwindows-amd64
CIPD client binary info:
{
  "client_binary":{
    "fetch_url":"https://storage.googleapis.com/chrome-infra-packages/store/SHA1/80bf92a4279f18dcfd775f7d7b9b8857cbdc07ca?GoogleAccessId=446031626781-otmjovfqg09mmp9a1v7sbk1827e9k38f%40developer.gserviceaccount.com&Expires=1477017390&Signature=y0ctdQoW4Gil8STumMZFOvbVz%2Ftf3K4HkFLtNNaUkxCGjQdWTNLXfPmg7Pr5XKleoXr%2BJFeDTH6nx2QrWfDBDaRfhzPvgf4%2FmTEQImctWnai8SLe2iv7W%2FtBe8JsPHPJ0YFwIcDVbJ%2BvjL8QE10ziwfz3lHKWNynT%2FhPFx2zTeE%3D",
    "sha1":"80bf92a4279f18dcfd775f7d7b9b8857cbdc07ca",
    "size":"12682240"
  },
  "etag":"\"hEBSnOc2yRu7qFkyDJD9yGeM11A/JTLUovbSwpMJaiGaiF79Vr0BaYw\"",
  "instance":{
    "instance_id":"bccdb9a605037e3dd2a8a64e79e08f691a6f159d",
    "package_name":"infra/tools/cipd/windows-amd64",
    "registered_by":"user:446450136466-p1anmb0n337qhh7u5sfsrbaq95ieks9p@developer.gserviceaccount.com",
    "registered_ts":"1464368295653400"
  },
  "kind":"repo#resourcesItem",
  "status":"SUCCESS"
}
GET https://storage.googleapis.com/chrome-infra-packages/store/SHA1/80bf92a4279f18dcfd775f7d7b9b8857cbdc07ca?GoogleAccessId=446031626781-otmjovfqg09mmp9a1v7sbk1827e9k38f%40developer.gserviceaccount.com&Expires=1477017390&Signature=y0ctdQoW4Gil8STumMZFOvbVz%2Ftf3K4HkFLtNNaUkxCGjQdWTNLXfPmg7Pr5XKleoXr%2BJFeDTH6nx2QrWfDBDaRfhzPvgf4%2FmTEQImctWnai8SLe2iv7W%2FtBe8JsPHPJ0YFwIcDVbJ%2BvjL8QE10ziwfz3lHKWNynT%2FhPFx2zTeE%3D
Fetched CIPD client infra/tools/cipd/windows-amd64:bccdb9a605037e3dd2a8a64e79e08f691a6f159d at C:\Users\Vadim\Downloads\depot_tools\cipd
[P6096 18:36:22.407 client.go:945 I] Packages to be installed:
[P6096 18:36:22.407 client.go:947 I]   infra/depot_tools/git_installer/windows-amd64:aa854a934e4d7fb24cc10b5d8b6f105494e16362
[P6096 18:36:22.407 client.go:824 I] cipd: resolving fetch URL for infra/depot_tools/git_installer/windows-amd64:aa854a934e4d7fb24cc10b5d8b6f105494e16362
[P6096 18:36:22.538 storage.go:249 I] cipd: initiating the fetch
[P6096 18:36:22.768 storage.go:214 I] cipd: about to fetch 29.4 Mb
[P6096 18:36:22.768 storage.go:205 I] cipd: fetching - 0%
[P6096 18:36:27.787 storage.go:205 I] cipd: fetching - 27%
[P6096 18:36:32.803 storage.go:205 I] cipd: fetching - 55%
[P6096 18:36:37.812 storage.go:205 I] cipd: fetching - 74%
[P6096 18:36:45.279 storage.go:205 I] cipd: fetching - 84%
[P6096 18:36:50.296 storage.go:205 I] cipd: fetching - 93%
[P6096 18:36:52.811 storage.go:205 I] cipd: fetching - 100%
[P6096 18:36:52.811 storage.go:205 I] cipd: fetching - 100%
[P6096 18:36:52.811 storage.go:221 I] cipd: fetch finished successfully
[P6096 18:36:52.811 client.go:779 I] cipd: successfully fetched infra/depot_tools/git_installer/windows-amd64:aa854a934e4d7fb24cc10b5d8b6f105494e16362
[P6096 18:36:52.936 deployer.go:131 I] Deploying infra/depot_tools/git_installer/windows-amd64:aa854a934e4d7fb24cc10b5d8b6f105494e16362 into c:\users\vadim\appdata\local\temp\tmputycep
[P6096 18:36:54.562 deployer.go:221 I] Successfully deployed infra/depot_tools/git_installer/windows-amd64:aa854a934e4d7fb24cc10b5d8b6f105494e16362
[P6096 18:36:54.577 client.go:1007 I] All changes applied.

Usage: gclient.py <command> [options]

---------------

It seems to be similar to your log.

AppData is some magical directory that doesn't appear in 'dir' listing of C:\Users\<name>, but exist anyway (try 'cd C:\Users\<name>\appdata').

Readonly folders in tmp is by design, I think. 

So far I'm suspecting that some Windows service is opening a handle to the temp directory and thus preventing it from being moved. It can be Windows Indexing Service, or Windows Defender, or something else.

For Indexing, please check that AppData is excluded from indexing: Start => "Indexing Options" => In "Included Locations" Users directory have 'AppData' excluded.

If this happens reliably, you may also try to catch the process that opens the handle (if any) by installing ProcessExplorer [1] and using its "Find Handle or DLL" feature (by searching for temp directory name).

ProcessExplorer: https://technet.microsoft.com/en-us/sysinternals/processexplorer.aspx

thanks for the info.

I already checked the indexing, and in windows 10, the AppData dir is
excluded by default. I ll check the other hypothesis today.

Any updates into checking your hypothesis?

it was MacAfee.

Can safely close.

This issue has been Available for over a year. If it's no longer important or seems unlikely to be fixed, please consider closing it out. If it is important, please re-triage the issue.

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