We have been transferring small files for several months without issue, but now we are trying to upload a file of about 2.5 GB. The transfer always fails with a message “Failed to write data to physical file” at random points. We only have 5GB of storage, but the folder shows that we have plenty of space. 

 We are using Windows Server 2025 and FileZilla CLI. 

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Windows PowerShell transcript start

Start time: 20250923160057

Configuration Name:

Machine: MCPA-TS (Microsoft Windows NT 10.0.26100.0)

Host Application: C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe -file  C:\PAO\FTP\Parcel_Fabric\parcel_fabric_ftp.ps1

Process ID: 9112

PSVersion: 5.1.26100.6584

PSEdition: Desktop

PSCompatibleVersions: 1.0, 2.0, 3.0, 4.0, 5.0, 5.1.26100.6584

BuildVersion: 10.0.26100.6584

CLRVersion: 4.0.30319.42000

WSManStackVersion: 3.0

PSRemotingProtocolVersion: 2.3

SerializationVersion: 1.1.0.1

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Transcript started, output file is C:\PAO\FTP\Parcel_Fabric\pslog.txt

1 Tue, 23 Sep 2025 20:14:12 GMT Starting upload of C:\Transfer\Parcel_Fabric\MC Parcel Fabric.zip

1 Tue, 23 Sep 2025 20:14:12 GMT Retrieving directory listing of "/"...

4 Tue, 23 Sep 2025 20:14:12 GMT ls

1 Tue, 23 Sep 2025 20:14:12 GMT Listing directory /

4 Tue, 23 Sep 2025 20:14:13 GMT put "C:\Transfer\Parcel_Fabric\MC Parcel Fabric.zip" "MC Parcel Fabric.zip"

4 Tue, 23 Sep 2025 20:14:13 GMT local:C:\Transfer\Parcel_Fabric\MC Parcel Fabric.zip => remote:/MC Parcel Fabric.zip

32 Tue, 23 Sep 2025 20:19:02 GMT Remote side initiated key re-exchange

32 Tue, 23 Sep 2025 20:19:02 GMT Doing Diffie-Hellman group exchange

32 Tue, 23 Sep 2025 20:19:02 GMT Doing Diffie-Hellman key exchange using 4096-bit modulus and hash SHA-256 (SHA-NI accel

erated) with a server-supplied group

32 Tue, 23 Sep 2025 20:19:03 GMT Initialised AES-256 SDCTR (AES-NI accelerated) outbound encryption

32 Tue, 23 Sep 2025 20:19:03 GMT Initialised HMAC-SHA-256 (SHA-NI accelerated) outbound MAC algorithm

32 Tue, 23 Sep 2025 20:19:03 GMT Initialised AES-256 SDCTR (AES-NI accelerated) inbound encryption

32 Tue, 23 Sep 2025 20:19:03 GMT Initialised HMAC-SHA-256 (SHA-NI accelerated) inbound MAC algorithm

2 Tue, 23 Sep 2025 20:23:10 GMT error while writing: received failure with description 'Failed to write data to physical

file:\MC Parcel Fabric.zip custID:77040981'

2 Tue, 23 Sep 2025 20:23:10 GMT File transfer failed after transferring 902,643,712 bytes in 537 seconds

1 Tue, 23 Sep 2025 20:23:10 GMT Starting upload of C:\Transfer\Parcel_Fabric\MC Parcel Fabric.zip

1 Tue, 23 Sep 2025 20:23:10 GMT Retrieving directory listing of "/"...

4 Tue, 23 Sep 2025 20:23:10 GMT ls

1 Tue, 23 Sep 2025 20:23:10 GMT Listing directory /

4 Tue, 23 Sep 2025 20:23:10 GMT reput "C:\Transfer\Parcel_Fabric\MC Parcel Fabric.zip" "MC Parcel Fabric.zip"

4 Tue, 23 Sep 2025 20:23:11 GMT reput: restarting at file position 901267456

4 Tue, 23 Sep 2025 20:23:11 GMT local:C:\Transfer\Parcel_Fabric\MC Parcel Fabric.zip => remote:/MC Parcel Fabric.zip

2 Tue, 23 Sep 2025 20:23:11 GMT error while writing: received failure with description 'Failed to write data to physical

file:\MC Parcel Fabric.zip custID:77040981'

2 Tue, 23 Sep 2025 20:23:11 GMT File transfer failed

Operation failed: Error (2)

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Windows PowerShell transcript end

End time: 20250923162311

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I am not familiar with FileZilla CLI. We will try to test it and update you later. I recommend that you test it with FileZilla GUI program first before you use a command-line script. Directly looking at the log, everything was fine except in the last step, it failed to save the file. You mentioned that it works fine with smaller files, so it seems to be related with the storage space not being enough. (Could you please email us your FileZilla CLI commands or script file?)

You have a group account on DriveHQ.com. The group account has enough storage space. But you tried to upload the file to a sub-account. In this case, the sub-user must have enough free storage space. The sub-account was allocated with a few GBs of storage space, it seems to be enough... but you already used a few GBs. Please allocate more space to the sub-account (I have done so for you. You can change it with the Group Admin feature).

FYI, DriveHQ has a command-line FTPS/SFTP client that you can use to upload very large files. It supports scripting. FTPS and SFTP are both very secure. Please visit:

https://www.drivehq.com/DriveHQ-KB/ftp/Command-line_FTP_Scripting.aspx

I just tested it and used it to upload a 5.5GB ISO file. It worked fine, please see the screenshot below: