Using Python '3.2.2 (default, Sep  4 2011, 09:07:29) [MSC v.1500 64 bit (AMD64)]' on Windows 7 Professional SP1:

If you set an access time for a file beyond Jan. 2038 on a file stored in a local NTFS filesystem, all's well:

>>> os.utime('c:\\temp_target\\ulp', (3433232323, 3433232323))
>>> os.stat('c:\\temp_target\\ulp')
nt.stat_result(st_mode=33206, st_ino=2251799813820060, st_dev=0, st_nlink=1, st_uid=0, st_gid=0, st_size=0, st_atime=3433232323, st_mtime=3433232323, st_ctime=1322133855)
>>> time.ctime(3433232323)
'Mon Oct 17 13:38:43 2078'

If you try to do this on a remote share (mounted as y:), provided by a Linux x64 box running Samba x64, things are different:

>>> os.utime('y:\\temp_target2\\ulp', (3433232323, 3433232323))
>>> os.stat('y:\\temp_target2\\ulp')
nt.stat_result(st_mode=33206, st_ino=67150103, st_dev=0, st_nlink=1, st_uid=0, st_gid=0, st_size=0, st_atime=910692730085, st_mtime=910692730085, st_ctime=1322133629)
>>> time.ctime(910692730085)
Traceback (most recent call last):
  File "<pyshell#22>", line 1, in <module>
    time.ctime(910692730085)
ValueError: unconvertible time

So, setting of access/modification time does not work - assumeably, we run into a 32-bit boundary somewhere...

Interestingly, if you set the respective access time from a Linux x64 box, you can see the right access time within Windows 7 via Explorer/Properties...

The timestamp is converted to time_t (32 bits) and then to FILE_TIME (64 bits). A function to convert directly a PyObject to FILE_TIME should be written.

bits).
> A function to convert directly a PyObject to FILE_TIME should be written.

I thought that time_t was 64 bits on Windows

> I thought that time_t was 64 bits on Windows

On Windows 64 bits, sizeof(time_t) is 64 bits and time.ctime(910692730085) works (return a string with year 2128).

It looks like Thorsten Simons is running Windows 32 bits.

> > I thought that time_t was 64 bits on Windows
time_t *is* 64bit by default since Visual Studio 8, even with the 32bit compiler:
http://msdn.microsoft.com/en-us/library/1f4c8f33(v=vs.80).aspx

> time_t *is* 64bit by default since Visual Studio 8

Ah? The issue was reported on a version compiled with Visual Studio 8. Notice "MSC v.1500" in:

> Using Python '3.2.2 (default, Sep  4 2011, 09:07:29)
> [MSC v.1500 64 bit (AMD64)]' on Windows 7 Professional SP1:

It's probably SAMBA which does not support time_t above 32bit.
st_atime=910692730085 corresponds to a FILE_TIME of 0x7fffffffffffffff

I found this samba bug: https://bugzilla.samba.org/show_bug.cgi?id=7785
It is fixed since Samba version 3.5.8.

Gentlemen,

thank you for your contribution - the information about the Samba fix solved the problem!