: While Build 3956 was a stable release, the final public version is 5.4.0 Build 3970 . Updating to this later build can sometimes bypass bugs present in earlier iterations of the 5.4.0 branch.
Given that FlashFXP is effectively dead and its "fixes" are dangerous, it is highly recommended to migrate to actively maintained FTP clients: flashfxp 540 build 3956 license key fix
Title: FlashFXP 5.4.0 Build 3956 — License Key Fix : While Build 3956 was a stable release,
: The developer was sentenced to 15 years in prison in 2017, effectively ending all official support and development. Verdict: Should You Use It? Verdict: Should You Use It
Build 3956 is an older version; the final public beta reached build 3970. Risks of "License Key Fixes"
: Some users have successfully retrieved updated keys via the FlashFXP Key Portal to bypass old validation errors, provided the site is reachable. Performance and Feature Review
The developer (Charles DeWeese/Bigstar) was sentenced to federal prison in 2017, effectively ending all future updates and official support.