Viterminal closes immediately after connecting?

Question

Windows

Viterminal Pro 5.1.1.2720 x64, server on Win 7 SP1 Home base x64.
Everything worked stably, but one day it stopped.
The client connects, the login window is displayed for a second and immediately closes.
In what a problem I can not understand. There are no similar problems on the support forum.
ViLicensesSrv log

ViLicensesSrv: 08:50:35: DEBUG: RestoreSessionKey 34BA80
ViLicensesSrv: 08:50:35: DEBUG: RestoreSessionKey 34BA10
ViLicensesSrv: 08:50:35: DEBUG: RestoreSessionKey 34BA80
ViLicensesSrv: 08:50:35: DEBUG: RestoreSessionKey 34BA10
ViLicensesSrv: 08:50:36: DEBUG: SrvNotifyDisconnect
ViLicensesSrv: 08:50:36: DEBUG: RestoreSessionKey 34BA80
ViLicensesSrv: 08:50:36: DEBUG: RestoreSessionKey 34B9A0
ViLicensesSrv: 08:50:36: DEBUG: RestoreSessionKey 34BA10
ViLicensesSrv: 08:50:36: DEBUG: pService->ReleaseConnect 1
ViLicensesSrv: 08:50:48: DEBUG: RestoreSessionKey 34BA10
ViLicensesSrv: 08:50:48: DEBUG: check this connection: hzdyS2fa4XuuiPLOWPH9RXtnUbs=FFFFFFFF, 127.0.0.1, hzdyS2fa4XuuiPLOWPH9RXtnUbs=FFFFFFFF, 0, res=1
ViLicensesSrv: 08:50:48: DEBUG: RestoreSessionKey 34BA80
ViLicensesSrv: 08:50:48: DEBUG: RestoreSessionKey 34BA10
ViLicensesSrv: 08:50:48: DEBUG: SrvNotifyNewServer
ViLicensesSrv: 08:50:59: DEBUG: RestoreSessionKey 34BA80
ViLicensesSrv: 08:50:59: DEBUG: RestoreSessionKey 34BA10
ViLicensesSrv: 08:50:59: DEBUG: RestoreSessionKey 34BA80
ViLicensesSrv: 08:50:59: DEBUG: RestoreSessionKey 34BA10
ViLicensesSrv: 08:51:00: DEBUG: SrvNotifyDisconnect
ViLicensesSrv: 08:51:00: DEBUG: RestoreSessionKey 34BA80
ViLicensesSrv: 08:51:00: DEBUG: RestoreSessionKey 34B9A0
ViLicensesSrv: 08:51:00: DEBUG: RestoreSessionKey 34BA10
ViLicensesSrv: 08:51:00: DEBUG: pService->ReleaseConnect 1

ViClient log

ViClient: 08:50:35: INFO: Попытка соединения с сервером
ViClient: 08:50:36: INFO: Соединение с сервером прошло удачно, создана новая сессия
ViClient: 08:50:36: INFO: Выход из приложения
ViClient: 08:50:59: INFO: Попытка соединения с сервером
ViClient: 08:51:00: INFO: Соединение с сервером прошло удачно, создана новая сессия
ViClient: 08:51:00: INFO: Выход из приложения