Found this in Xeams.log - environment is the SYNAVM01 virtual machine (plus whatever upgrades applied automatically)

2017-12-08 16:05:01,942 ERROR l.e - Exception caught calling CLAMD on localhost/127.0.0.1: Read timed out
java.net.SocketTimeoutException: Read timed out
	at java.net.SocketInputStream.socketRead0(Native Method)
	at java.net.SocketInputStream.read(Unknown Source)
	at java.net.SocketInputStream.read(Unknown Source)
	at sun.nio.cs.StreamDecoder.readBytes(Unknown Source)
	at sun.nio.cs.StreamDecoder.implRead(Unknown Source)
	at sun.nio.cs.StreamDecoder.read(Unknown Source)
	at java.io.InputStreamReader.read(Unknown Source)
	at java.io.BufferedReader.fill(Unknown Source)
	at java.io.BufferedReader.readLine(Unknown Source)
	at java.io.BufferedReader.readLine(Unknown Source)
	at l.e.a(ClamAVClient.java:524)
	at com.synametrics.xeams.rulesengine.custom.VirusDetector.a(VirusDetector.java:213)
	at com.synametrics.xeams.rulesengine.custom.VirusDetector.parseMessage(VirusDetector.java:52)
	at com.synametrics.xeams.rulesengine.y.a(RulesProfile.java:5849)
	at com.synametrics.xeams.rulesengine.y.c(RulesProfile.java:2928)
	at com.synametrics.xeams.rulesengine.y.a(RulesProfile.java:2275)
	at com.synametrics.xeams.connector.d.a(ProxyConnector.java:104)
	at D.e$2.run(SmtpProxyWorker.java:704)
	at java.lang.Thread.run(Unknown Source)
2017-12-08 16:05:01,944 ERROR custom.VirusDetector - Exception caught

Andrew,

How often do you see this message? It just means ClamAV took longer than expected to determine if a virus was found in the message and the client (Xeams in this case) timed out.

Frequency is variable - have not seen this for some weeks and then it turned up 3 times in 5 mins when processing an EICAR test stream of messages.