@Willi: This should be fixed in the latest release:
Issue 1764 – Cannot upload files over 50GB to S3

Error:

Part number must be an integer between 1 and 10000, inclusive Zusätzliche Details: ArgumentName: partNumber, ArgumentValue:

Thanks, Martin, the problem is gone in the latest beta.

@Marko: Thanks for your report.
I have sent you an email with a debug version of WinSCP to the address you have used to register on this forum.

Hi Martin,

I'm using the latest (5.13.4) portable version and I'm getting the same error when trying to copy a file larger than 2 GB, despite that this bug #1636 was supposed to be fixed (Issue 1636 – Failure when uploading a file larger than 2GB using S3 protocol).

It happens when trying to copy via the GUI on Windows Server 2008 R2. Smaller files work okay.

EDIT: Attached debug log.

Thanks and regards,
Marko

Hi Martin,

The new version you sent appears to fix the problem, thanks.

I successfully uploaded two 4GB files to S3 today, without any problems.

My colleague, who initially alerted me to the problem, was not successful on several attempts, claiming the uploads failed spontaneously variously at 40–70% complete – but I'm uncertain if his machine tried to sleep, or his internet access service glitched or whether the ongoing slow upload rate (about 2Mb/s I guess, it is an old HFC service) had an impact. I'll ask him to have another go, and report back.

Regards,
Daniel

Sorry for delay and thanks for your report.

This bug has been added to the tracker:
Issue 1636 – Failure when uploading a file larger than 2GB using S3 protocol

I'm sending you an email with a development version of WinSCP to the address you have used to register on this forum.

Hi Martin,

Uploads of very large (video) files to S3, apparently >2GB, fail with a error box saying:

Error reading file D:\Users\filepath\file.mov
System Error. Code 998.
Invalid access to memory location

Uploads of less than 2GB or thereabouts on the same filesystem work fine (working examples were 1.6GB). Files can be opened locally in other tools.

Observed on WinSCP 5.13 (Build 8172) on Windows 7 Enterprise SP1
Also observed on WinSCP 5.13.1 (Build 8265) on Windows 7 Professional SP1

Upgraded WinSCP to get S3 functionality, so cannot refer to earlier behaviour.
Protocol: S3
Interface mode: GUI, using Commander Mode

Steps to reproduce:

• Find or create a local file greater than 2GB.
  
• Navigate to local and remote (S3) directories.
  
• Drag local file onto S3 side of the commander interface
  
• Transfer popup window appears, then the Error popup window appears within a second.
  

I've attached a log and a screenshot.

Thanks for looking at this.
Daniel