Premature Expiration: Download limit = 1 (8.1.3 Linux)
Posted: Fri May 08, 2026 3:12 pm
We are experiencing an issue with Wing FTP Server weblinks when the Download Limit parameter is set to 1.
When using Google Chrome, the weblink often expires before the user can complete the actual download. Based on analysis, this appears to be caused by modern browser and endpoint security behavior rather than user error. Chrome performs background requests (e.g., prefetch/speculative GETs) and Microsoft Defender SmartScreen may also initiate preliminary download or inspection requests.
These requests are indistinguishable from a real download attempt at the server level and appear to decrement the weblink’s download counter immediately. As a result, the single allowed download is consumed before the user-initiated download begins. This makes Download Limit = 1 unreliable with current browser/security stacks.
At present, the only viable workaround is setting Download Limit ≥ 2 and relying on expiration time instead, which weakens the intended “single-use” control.
Please confirm whether WingFTP enforces the limit based on the first valid request (and not completed downloads). Ideally you could change the logic to ignore prefetch/scanner requests and count ONLY actual completed downloads.
Thanks!
Eric
When using Google Chrome, the weblink often expires before the user can complete the actual download. Based on analysis, this appears to be caused by modern browser and endpoint security behavior rather than user error. Chrome performs background requests (e.g., prefetch/speculative GETs) and Microsoft Defender SmartScreen may also initiate preliminary download or inspection requests.
These requests are indistinguishable from a real download attempt at the server level and appear to decrement the weblink’s download counter immediately. As a result, the single allowed download is consumed before the user-initiated download begins. This makes Download Limit = 1 unreliable with current browser/security stacks.
At present, the only viable workaround is setting Download Limit ≥ 2 and relying on expiration time instead, which weakens the intended “single-use” control.
Please confirm whether WingFTP enforces the limit based on the first valid request (and not completed downloads). Ideally you could change the logic to ignore prefetch/scanner requests and count ONLY actual completed downloads.
Thanks!
Eric