Message : The IPMI device driver attempted to communicate with the IPMI BMC device during normal operation. However the communication failed due to a timeout. You can increase the timeouts associated with the IPMI device
The registry key helps increase the timeout duration but it may not able to solve the error if it simply fail to "communicate with the IPMI BMC device".
I suggest you to check if the driver loaded successfully as the article mentioned:
Click Start, then click on Start Search.
Type Device Manager and click Enter to open the Device Manager window.
Open the System devices node and locate Microsoft Generic IPMI Compliant Device.
Note whether there is an exclamation mark beside the device name. If there is no exclamation mark, the driver has loaded successfully.
If IPMI is actually not needed, you can uninstall it as mentioned in this article (for Windows 2003 so just for reference)
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