Several weeks ago, suddenly I cannot connect to Astrill VPN in StealthVPN mode when using its TCP mode. I remembered that all I’ve done in the network area was installing an old version teamviewer. So I uninstalled the old version of teamviewer, installed a newer version of teamviewer and tried to connect to Astrill VPN in StealthVPN mode by using its TCP mode, it works!
Though I still think that old version of teamviewer may not be the cause of failing connect to Astrill VPN, I don’t want to figure out the root cause now. Because I don’t have time to do it. 😛