Troubleshooting slow file copying in Windows

What does this guide do?

Helps you diagnose and resolve the issue of slow file copy in your organization.

Who is it for?

Administrators who help diagnose and resolve slow file copy issues.

How does it work?

We’ll begin by determining the cause of your issue. Then we’ll take you through a series of steps that are specific to your situation.

Estimated time of completion:

15-30 minutes.

Determine the cause of the issue

Slow file copying can be caused by storage issues, client issues, and server issues. Please follow these steps to determine the cause of the issue:

  1. On the file server that hosts the shared folder, copy the file to its local hard disk. If the file-copying speed is unusually low (that is, obviously slower than average speed), select Storage as the cause. If the speed is typical, go to step 2.
  2. Use another client computer to copy the files from or to the shared folder.

    If the file copy speed is still slow, select Server as the cause.

    If issue does not occur, select Client as the cause.

What is the cause of the issue?

Determine the cause of the issue

Slow file copying can be caused by storage issues, client issues, and server issues. Please follow these steps to determine the cause of the issue:

  1. On the file server that hosts the shared folder, copy the file to its local hard disk. If the file-copying speed is unusually low (that is, obviously slower than average speed), select Storage as the cause. If the speed is typical, go to step 2.
  2. Use another client computer to copy the files from or to the shared folder.

    If the file copy speed is still slow, select Server as the cause.

    If issue does not occur, select Client as the cause.

What is the cause of the issue?

Update the driver for your storage

To resolve this issue, try to update the driver for your storage. If the issue still occurs, contact the driver manufacturer for additional troubleshooting.


Did this solve your problem?

Verify the kind of the shared folder

To verify the kind of the shared folder, open the properties of the shared folder. For the DFS shared folder, the DFS tab is displayed.

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Is the target folder a DFS (Distributed File System) shared folder?

Determine whether the problem is caused by the DFS path

Please try to use the UNC path instead of the DFS path to open the shared folder. Then, you can check whether the issue still occurs. This step can help you determine whether the problem is caused by the DFS path.

How to determine the UNC path of the DFS shared folder:

  1. Right-click the shared folder, and then select Properties.
  2. On the DFS tab, you see the UNC path in Referral list.
    3860_image4
     


Is it slow when you use the UNC path instead of the DFS path?

Verify the DFS referrals

To verify the DFS referrals, follow these steps:

  1. Right-click the shared folder, and then select Properties. On the DFS tab, locate all active referrals.
  2. Remove UNC paths that are not active or servers that are not reachable or are removed.
  3. Connect these paths one by one, and make sure that all destination paths can be reached directly from the client. By design, if the client can’t connect the first referral, it will switch to the second and so on. This will create a delay.

Did this solve your problem?

When does the slow file copying problem occur?

Please select one of the following scenarios:

Resolutions for the non-DFS shared-folder issue

To resolve this issue, follow these steps on the client computer that has the problem:

  1. Delete the third-part network provider from client computer. The default options are as follows. (Any additional provider can be considered as a third party.)
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  2. Remove additional values from the following registry keys:

    Open Registry Editor. Located the following keys. Each key contains a Provider Order value.

    HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\NetworkProvider\HwOrder

    HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\NetworkProvider\Order


    Check to make sure that each Provider Order value has only three values: “RDPNP,” “LanmanWorkstation,” and “webclient.”
    3860_image6
     
  3. Compare the settings of Jumbo Frames and Large send offload with the settings on working computers. and adjust the settings of Jumbo Frames and Large send offload accordingly. (If it is disabled, enable it, and then check whether that helps)
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  4. Make sure that the workstation service is running.
  5. Make sure that client for Microsoft networking is selected in the network connection properties.
    3860_image8
     


Did this solve your problem?

Slow performance when you copy a folder or multiple files

If you compare the copying time for a folder that contains multiple files with the copying time for a file of the same size, copying the folder will always require more time. This is expected behavior. And the more files that are in the folder, the slower the file-copying process.


Did this solve your problem?

Install the hotfixes for the file server that hosts the shared folder

For Windows Server 2008 or Windows 7, install all the hotfixes that are described in KB 2473205.

For Windows Server 2012 or Windows 8, install all the hotfixes that are described in KB 2899011.


Did this solve your problem?

Resolution for server-side issues
  1. Check whether the client is connected to a remote/WAN DFS server. (Ideally, it should be connected to the local site DFS server). If it is connected, double-check the site and subnet mapping in Active Directory Sites and Services. If subnets are not mapped correctly, DFS will give an incorrect priority to remote DFS servers while it presents referrals.
  2. Make sure that the local DFS server is working.
  3. Set the Referral ordering Method for DFS namespace root referrals to Lowest Cost.
  4. If IPv6 is enabled in the environment, configure IPv6 subnets in Active Directory Sites and Services. Or, as a workaround, disable IPv6 in the environment.

How to determine the referral DFS server to which the clients are connecting:

  1. On a client computer, right-click the shared folder, and then select Properties.
  2. On the DFS tab, check the referral list. The current DFS server is marked as active. In the following example, the client is connecting to the server HAOMS1.
    3860_image4
     


Did this solve your problem?

Congratulations!

Your slow file copying issue is resolved.

Sorry

It appears that we are unable to resolve your issue by using this guide. For more help resolving this issue please see our TechNet support forum or contact Microsoft Support.

خصائص

رقم الموضوع: 10118 - آخر مراجعة: 04‏/05‏/2016 - المراجعة: 24

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