Data transfer

Question

I was copying my files 600 GB data one folder to external harddisk so it was copying about 90% but it cancelled by mistake. So can you please help how to restart my remaining copying files remaining 10% ...

Answer 1

Hi,

You don’t need to start the full 600 GB transfer again. You can resume the remaining files safely using one of these methods:

1. Use File Explorer

Just start copying the same source folder to the external drive again.

When Windows detects existing files, it will show a prompt:

“Replace the files in the destination / Skip these files / Let me decide for each file.”

Choose “Skip these files” → Windows will only copy the files that are missing (your remaining ~10%).

2. Use Robocopy (recommended for large transfers)

(Robocopy | Microsoft Learn)[https://learn.microsoft.com/en-us/windows-server/administration/windows-commands/robocopy]

If you want a more reliable, resumable transfer:

1. Open Command Prompt.
2. Run this command:

robocopy "C:\Path\To\SourceFolder" "E:\DestinationFolder" /E /Z /R:1 /W:1

What the switches mean:

• /E – copy all subfolders
• /Z – resume mode (can continue if interrupted)
• /R:1 – retry once if a file is locked
• /W:1 – wait 1 second between retries

Robocopy will only copy the files not already copied, and it can automatically resume if interrupted again.

---

Hope this helps.

Answer 2

To restart the copying of your remaining files after a cancellation, you can use the Data Movement library, which allows you to resume transfers that were interrupted. Here’s how you can do it:

1. Persist Transfer Progress: Ensure that the transfer progress was saved to disk. This allows you to resume the transfer from where it left off.
2. Initialize TransferManager: Create a TransferManager object configured to resume the transfer. You will need to specify the appropriate StorageResourceProvider instances.
3. Resume Transfer: Call the ResumeTransferAsync method of the TransferManager, providing the transfer ID of the interrupted transfer.

Here’s a code snippet to illustrate:

// Create a token credential
TokenCredential tokenCredential = new DefaultAzureCredential();

TransferManager transferManager = new(new TransferManagerOptions()
{
    ProvidersForResuming = new List<StorageResourceProvider>()
    {
        new BlobsStorageResourceProvider(tokenCredential)
    }
});

// Resume the transfer using the transfer ID
TransferOperation resumedTransfer = await transferManager.ResumeTransferAsync(transferId: "YOUR_TRANSFER_ID");

Make sure to replace "YOUR_TRANSFER_ID" with the actual ID of the transfer you want to resume. If you do not have the transfer ID, you can retrieve it using the GetTransfersAsync method.

This approach will help you continue from where the transfer was interrupted, rather than starting over from scratch.