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In Ignition, dragging a tag into the Tag Browser changes status to Uncertain_LastKnownValue

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Symptoms:

In Ignition, when you drag a tag with a known good quality to the Tag Browser, the quality of the tag may change to Uncertain_LastKnownValue. If you review the wrapper logs, you may find messages similar to the following:

java.lang.InternalError: a fault occurred in a recent unsafe memory access operation in compiled Java code
    at io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.read(AbstractNioByteChannel.java:136)
    at io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:788)
    at io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:724)
    at io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:650)
    at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:562)
    at io.netty.util.concurrent.SingleThreadEventExecutor$4.run(SingleThreadEventExecutor.java:994)
    at io.netty.util.internal.ThreadExecutorMap$2.run(ThreadExecutorMap.java:74)
    at java.base/java.lang.Thread.run(Unknown Source)

Workaround:

Contact Product Support (by email, support@opto22.com) for instructions on a workaround.

Resolution:

Opto 22 has resolved this issue.

Questions?

Contact: Opto 22 Product Support.
Phone: 800-835-6786 or 951-695-3080
Email: support@opto22.com

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