# Troubleshooting NVRAM or Socket Errors on NextSeq 500/550

**Initialization can fail with one of the following error types:**

* While attempting to initialize communication with firmware prior to reading device settings from NVRAM. (System.Net.Sockets.SocketException)
* Socket error on TCP port 192.168.113.2:5555 (System.Net.Sockets.SocketException)
* “A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond 192.168.113.2.5555Error code is “10060”

Example of possible errors:\
![](/files/zO7xpbnnyS4ObiJezadV)

**Cause**: These errors are due to internal network errors. The NextSeq 500/550 has two network interface cards (NIC). One connects the instrument to the external network, and the second connects the Single Board Computer (SBC) to the hardware control computer Main Printed Circuit Assembly (MPCA).

For assistance, contact [Illumina Technical Support](https://www.illumina.com/company/contact-us.html#/united-states/technical-support).

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| *For any feedback or questions regarding this article (Illumina Knowledge Article #1391), contact Illumina Technical Support* [*techsupport@illumina.com*](mailto:techsupport@illumina.com?subject=Question%2FFeedback%20Regarding%20Illumina%20Knowledge%20Article%20#000001391%20-%20Instrumentation%20\&body=Dear%20Illumina%20Technical%20Support,%0D%0A%0D%0A)*.* |


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