Large File Copy Fix

From INIwiki
(Redirected from Windows/Large File Copy Fix)
Jump to: navigation, search


[edit] Here's the problem:

Maybe you have already encountered the strange behavior that it takes much longer to copy large files in Windows Vista than in Windows XP. You thought that the change from XP to Vista would at least be not a disadvantage speed wise but Vista somehow seems to have a problem copying large files. This happens especially with mapped drives but it could also be that you witness network disconnects.

[edit] Here's the cause:

The problem is caused by a new feature called Auto Tuning which is by default enabled in Microsoft Windows Vista. What Auto Tuning does is that it reacts on changes in the network by tuning the receive windows size. The solution would be of course to disable Auto Tuning in Vista. Some users reported that disabling Auto Tuning had a positive effect on their ability to connect to services such as Windows Live Messenger which did not work before.

[edit] Here's a fix:

To disable Auto Tuning and speed up the copy process and avoid timeouts and disconnects do the following:

Open a command prompt and type the following:

netsh int tcp set global autotuninglevel=disabled

To turn it on again:

netsh int tcp set global autotuninglevel=normal

I've tried this and it seems to help matters and doesn't seem to have any nasty side-effects (that I can see) but I think we need to wait for a patch (or maybe even SP1) before we get a proper fix for this problem. Share and Enjoy:These icons link to social bookmarking sites where readers can share and discover new web pages.

[edit] Source

The PC Doctor - Adrian W. Kingsley-Hughes

[edit] MS Supplied Patch

KB Article Can be found here:

Slashdot Article

TechNet Postings:

Patch can be found here:
search for 931770 on the page then choose OS type

x86 version can be downloaded here:
Personal tools