Problem when copying large files (Vista 64)

I am encountering a strange issue in Vista x64 when copying large (~5gb or more) files. The computer will copy about the first half of the file normally, then it will absolutely slow to a crawl. Windows Explorer stops responding, I experience severe mouse and keyboard lag, and even task manager is very slow to respond. When I do get it open, I notice that the simple act of copying a file is using 99-100% of my RAM, and suspect that this might have something to do with the slowness.

At first, I suspected something might be wrong with my hard drive, but this same exact behavior occurs when copying from one flash drive to another and bypassing the hard drive entirely. Also, strenuous disk activity by any program other than the OS itself (for instance, extracting or compressing a similar-sized file with 7zip) never causes slowdowns. What's worse, when whatever I'm copying finally finishes, normal performance does not return until I suffer through the lag and re-boot the machine. Even shutting down becomes ridiculously slow. The hard drive light also stays on pretty much non-stop when the lag begins to occur, and if I listen very closely, I can hear it constantly doing something (which I shouldn't, especially when the file copying only involves USB drives).

I have run a full scan with both MSE and Malware Bytes and found nothing. Is this just one of the "inefficiencies" of Vista and a reason to upgrade, or is there something somewhere I can change to hopefully fix this.

 

You need to use a program call unlocker. It is a program that allows you to move files that windows won't let you, but I recall having a similar issue you had and using unlocker helped me got rid of it. At the time I had a 32bit OS so I don't know if it works for a 64bit OS.

UNLOCKER 1.8.9 BY CEDRICK 'NITCH' COLLOMB

 

The files in question are mostly DVD images or large archives which I have created myself. Why would Windows be preventing my from copying them?

I am usually not trying to delete them at the same time; I am simply copying them (usually from one computer to another, by way of flash drive). Even if a file is in use, Windows will let me copy it.

 

Well, it would appear that I have found a fix for this, if anyone else is having the same issue. Open a command prompt and type the following:

bcdedit.exe /set {current} nx AlwaysOff

and restart. I'm about halfway through copying a 55 gb disk image as a test and no freeze yet. RAM usage is also way down from where it used to be (a little over 1 gb instead of 3.99 gb). Previously, my computer would have been totally unresponsive by this point.

 

Me ( win 7 ultimate 64 bit ) , my brother ( win 7 home pro ) , a few friends of mine ( win vista 32-64 bit ) and a few more people that i know can not transfer files bigger than 5GB. I had the same problem is already mentioned above . I will try this command and i hope it works .
Btw i was solving that problem by using winrar for spliting the files in 2 GB each part .

This command does not work to me . I 've tryed it in the normal run window, cmd window , start button . None of those did not accept that line . And i was trying to transfer 6.2 GB iso from my laptop to my phone @ USB . When i tryed this by bluetooth it was ok .

 

Did you make sure to run the command prompt as an administrator and restart the computer afterwards?