I recently had to diagnose a computer that could not connect to a Microsoft Dynamics NAV Environment. The below message was returned;

The client could not establish a connection to the Microsoft Dynamics NAV Server.

Fault Code = ‘InvalidSecurity’

Reason = ‘An error occurred when verifying security for the message.’


After some digging I noticed the time was wrong on the computer. The Windows time service was disabled for some reason.

I set the Windows time service back to Automatic startup and started the service.

A reboot would have probably resolved the issue at this point but I ran “w32tm /resync /nowait” to force a time sync.

If the time is still not updating correctly take a look at this post