https://community.splunk.com/t5/Monitoring-Splunk/ERROR-TcpOutputFd-TcpOutEloop-Read-error-An-existing-connection/m-p/762003#M11155 <P>ERROR TcpOutputFd [TcpOutEloop] - Read error. An existing connection was forcibly closed by the remote host.</P><P>I have this error on one of our Splunk Windows UF, and I cannot resolve the issue.</P><P>our setup is UF&gt;Intermediate HF&gt;HF&gt;Indexer</P><P>1. Connection from the UF to the intermediate HF port 9997 is okay, using tnc.</P><P>2. tried re installing the UF and restarting the Intermediate HF but still no success.</P><P>3. I noticed that from intermediate HF, its only sending SYN_RECV packets to UF.</P><P>&nbsp;</P><P>Please help to check.<BR />balshore</P><P>&nbsp;</P><P>&nbsp;</P> Tue, 30 Jun 2026 08:35:42 GMT Balshore 2026-06-30T08:35:42Z https://community.splunk.com/t5/Monitoring-Splunk/ERROR-TcpOutputFd-TcpOutEloop-Read-error-An-existing-connection/m-p/762003#M11155 <P>ERROR TcpOutputFd [TcpOutEloop] - Read error. An existing connection was forcibly closed by the remote host.</P><P>I have this error on one of our Splunk Windows UF, and I cannot resolve the issue.</P><P>our setup is UF&gt;Intermediate HF&gt;HF&gt;Indexer</P><P>1. Connection from the UF to the intermediate HF port 9997 is okay, using tnc.</P><P>2. tried re installing the UF and restarting the Intermediate HF but still no success.</P><P>3. I noticed that from intermediate HF, its only sending SYN_RECV packets to UF.</P><P>&nbsp;</P><P>Please help to check.<BR />balshore</P><P>&nbsp;</P><P>&nbsp;</P> Tue, 30 Jun 2026 08:35:42 GMT https://community.splunk.com/t5/Monitoring-Splunk/ERROR-TcpOutputFd-TcpOutEloop-Read-error-An-existing-connection/m-p/762003#M11155 Balshore 2026-06-30T08:35:42Z