"550... Overwrite permission denied" when FTP uploading zip files through SWG and ISA 2006 Server

Products

• Web Gateway

Issue/Introduction

FTP uploads outbound through Symantec Web Gateway proceed slowly and/or stop.

"550... Overwrite permission denied" appears in either an FTP client or in a packet capture recorded during the reproduction of slow upload symptoms

Cause

SWG Appliance fails to handle TCP windowing appropriately.

Resolution

Symantec reproduced this symptom in a test lab environment and will address this issue in a forthcoming build.

To workaround this behavior, Symantec recommends that you disable TCP windowing at either endpoint of the FTP conversation.
Please see the following third party documentation for steps:
http://www.ecr6.ohio-state.edu/window-scaling.html