Activation and Update Check problems

[dbengali]

I have purchased free file sync donation edition, and I am having an issue -

When I start the program, it says unable to activate, giving the error Invalid HTTP response: ""

I am able to activate offline by copying and pasting the provided URL and then entering the code, but often after a while, this issue comes up again, and I have to repeat the procedure.

When the program opens, it says Cannot find FreeFileSync version number online. A newer version is likely available. Check manually now? Invalid HTTP response: ""

In the menu bar I see ? FreeFileSync Unknown is available! ? as the last entry

I have been having this problem with FFS 10.10 on Mac OS 10.14.4, so I purchased the donation edition of FFS 10.11, but the problems remain.

Also in the title bar, the app does not say Donation Edition, but in the about window it does.

I am not running any third-party firewall software or internet filtering software, and I have encountered this issue while in multiple locations, connecting to the internet via multiple networks.

[Zenju]

There must be some software component blocking access like:
viewtopic.php?t=5666
If there were an ordinary web access problem, the error message would be different.

[dbengali]

thanks, I haven't changed any software, but it is now working. I am currently on a different network than the last time I ran FFS and encountered the issue however. Could I ask what address needs to be reachable in case it is something that is being blocked in some cases but not others?

[Zenju]

The activation also directly connects with freefilesync.org