SoftEther does not connect over TCP after reinstalling Windows

I am using SoftEther VPN for a long time. Recently I have reinstalled the Windows and it does not connect using TCP, and just connects over UDP.

When I try to connect over TCP, the software instantly (it is so fast, that I believe it doesn't try to reach over network, and it is local problem!) shows following error message:

Error (Error Code 2):
Protocol error occurred. Error was retued from the destination server.

I shall mention that I have encountered this problem once before, and at that time reinstalling the windows solved the problem (and I didn't get the real problem). But now even in the refresh installation it does not work.

I am using Windows 8.1.

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