The Zarnecki Incursion - S4-E19
Plot hole: If Howard can hack into Blizzard's database so deeply that he can get the name and address of game players, he could easily restore all of Sheldon's stolen 'items'. Hacking personal details - a player's real identity and their home address! - is hardcore, detailed work that only an expert could do, compared to which adding a few extra items to a player in the game would be child's play. Sheldon would not be concerned about a possible comeback from the administrators at Blizzard. First, Sheldon doesn't hack into the database, Howard does, and someone as pragmatic and self-centred as Sheldon would simply disclaim any responsibility. Second, hacking into another player's account to access highly sensitive personal information like their home address would risk incurring the same penalty from Blizzard anyway. Either Sheldon doesn't know that or he doesn't care. Third, his account has already been hacked when the virtual items were stolen. He could simply claim that Howard's hacking into his account was just more of the same - nothing to do with him. Fourth, Blizzard did not detect the hacker stealing Sheldon's virtual items, nor did they prevent it happening, and they did not detect Howard hacking into his account to obtain his name and address. Sheldon can rightly assume he has nothing to fear.
The Hot Troll Deviation - S4-E4
Factual error: Howard's claim that characters in World of Warcraft can engage in sexual activities is wrong, also while there is a Bridge of Souls currently in the game, there is no way to get under it.
Suggested correction: I can only assume you have never played on a RP server? ERP is a big thing, some players even make gold from it.
The Benefactor Factor - S4-E15
Continuity mistake: When Sheldon and Leonard are in the kitchen discussing Leonard's upcoming night out with Mrs. Latham, there's a plastic bottle of orange juice on the table that keeps disappearing and reappearing as the camera switches between Sheldon and Leonard.
Suggested correction: The bottle is there every time, a few times because of the camera angle it is hidden by Sheldon.
The bottle of OJ is right next to a container of Coffee Mate, both items always visible when the bottle of OJ is present. When the OJ is not present, only the Coffee Mate is there, near enough the center of the table to not possibly be blocked out by either Sheldon nor Leonard.
No it is not right next to the coffee Mate, there is some distance with a phone in between. You can sometimes see the bottle behind Sheldon when he moves.
The Zarnecki Incursion - S4-E19
Character mistake: As they drive to Todd Zarnecki's to confront him, Sheldon says, "I almost feel sorry for the poor fool, sitting in his split-level suburban ranch..." Architecturally, split-level (technically three levels joined by half flights of stairs) and ranch (single level) are separate and distinct designs. There is no "fusion" of the two. I can't help but think Sheldon would have corrected anyone who said the same thing.
Suggested correction: Actually the term "split level ranch" is used to describe a house that has one full floor above ground and a partial lower level, vs the traditional split level house which has a full floor above ground, a second partial floor and a partial lower level.
Suggested correction: Hacking the database to return items to Sheldon's account would also be traceable to Sheldon's account as cheating. That would get him permabanned if discovered, not a risk Sheldon wants to take.
LorgSkyegon
First, Sheldon doesn't hack into the database, Howard does, and someone as pragmatic and self-centred as Sheldon would simply disclaim any responsibility. Second, hacking into another player's account to access highly sensitive personal information like their home address would risk incurring the same penalty from Blizzard anyway. Either Sheldon doesn't know that or he doesn't care. Besides, if Blizzard were aware that Howard had hacked into Sheldon's account, why weren't they aware that the person who stole the virtual items did?
Reading information from a server is easier than writing new data into it. You can steal a mass bulk of files and extract the information at a later time, whereas writing information in Sheldon's account would take much more precision.