The LG LRM_519 is a DVD recorder with Tuner and record to HDD. It can also be configured to [Send to PC] recording if the Windows 7 machine has been configured to be a member of a Workgroup, not a Domain and HomeGroup filesharing is not turned on.
In addition, the IPSec MMC plug-in which can be exposed (only) by creating a new MMC console and then Adding the IIPSec plugin can host a rules called [ WND ] which will block SMB connections by default and enormously slow down "Kerberos" authenticated logins, or any password authenticated logins.. in fact it will stop "correct" username /password authenticated logins in many cases.
The problem appears to be enforcement of a "Kereberos" specifc rules that lingers after passing through a Domain joined phase.. or because of an erroneous windows patch, which happens quite often.
Rather than reinstalling the machine, created a new mmc.exe instance, add in the IPSec ruleset plugin (which is not the same thing as the Firewall IPSec plugin, nor is it the same thing as the IPSec VPN connection tool.. this is a legacy totally off the radar plugin, which also buries and does not expose is rules sets.. unless it is specifically exposed by digging in the IPSec plugin.. all rulesets appear blank until highlights, and the Inbound set is clicked on and then refreshed.. quite hidden.. quite bad programming.