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Description This article discusses about 'Unable to connect to the update server' logs in FortiClient EMS server.
Scope FortiClient EMS server 6.4.x and above.
Solution btan_0-1662952801616.png


This log indicates that FortiClient EMS failed to retrieve antivirus signatures update from the public FortiGuard Distribution Server (FDS).

There is maybe network latency and timeout on connection to the FDS and at TCP port 80.

FortiClient EMS attempts to retrieve updates every hour.

As long as this is not happening every hour (which indicates genuine connection issue), it is not an issue.
It is safe to ignore the message.

It is possible to check whether the signature is up-to-date or not from FortiClient EMS settings -> FortiGuard services -> View signature list.

Compare it with the latest version in


If FortiManager is used to update signature, check on FortiManager connectivity: