AstraSync is unable to connect to the network or is not getting a response from the server. Try to reboot the device and try again. If the issue persists, try changing the Cellular Connection under Menu > Options > Network Settings.
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If there are problems on the carrier network then AstraSync will be unable to connect. Normally such outages are resolved quickly and AstraSync will resume working without intervention. Run the ‘Detect Network’ test within Options > Network settings, to see which connection options are available.
If the problem continues you should verify you have the correct server entered within AstraSync > Menu > Server Configuration. If that doesn't help contact your carrier and request the Service Books are deleted/resent to your device