You experience a Bug Check 0x124 (WHEA_UNCORRECTABLE_ERROR) on a system with Symantec Endpoint Protection (SEP).
SEP (all versions)
This bug check is typically related to physical hardware failures. It can be heat related, defective hardware, memory or even a processor that is beginning to fail or has failed. If over-clocking has been enabled, try disabling it. Confirm that any cooling systems such as fans are functional.
Run system diagnostics to confirm that the system memory is not defective. It is less likely, but possible that a driver is causing the hardware to fail with this bug check.
Hence, it is unlikely (albeit not impossible) the issue is related to SEP. For example, in some of the instances that were reported to us, the issue was found to be caused by an outdated version of igdkmd64.sys (Intel Graphics Kernel Mode Driver) and could be resolved by downloading and installing the latest Intel HD Graphics driver via the hardware vendor's web site. As vendors tend to fix issues like these at some point, it may very well be caused by another oudated driver at this point in time.
Whenever this issue occurs, in addition to making sure the operating system is fully up-to-date in terms of Windows Updates, it is always recommended to first install all the latest drivers available via the hardware vendor's web site. If that should not resolve the issue, consider upgrading to the latest version of SEP, to ensure all SEP drivers are the latest and greatest.