Expecting Value Line 1 Column 1 (char 0) Error Description
Mac users who have suddenly encountered a warning message stating 'Expecting value line 1 column 1 (char 0)' might be feeling a bit perplexed. The error can be a perfectly legitimate one that sometimes occurs after installing one of the big macOS updates. It seems, however, that a more common cause is the presence of a PUP (Potentially Unwanted Program) or a malware threat on the user's system.
Users almost never download PUPs willingly as these types of apps offer deceptive features or are barely functional. For that reason, PUPs rely on dubious distribution tricks to spread themselves without attracting the attention of the user. Two of the most prolific types of PUPs that have been targeting Apple users, and more specifically Mac users, are browser hijackers and adware. While both are considered low risk as they do not pose a direct threat to the system they are installed on, their presence still leads to a considerable increase in the security risks faced by the user.
Adware apps are tasked with running intrusive advertising campaigns that can oftentimes lead to unsafe third-party websites. Browser hijackers, on the other, hand establish control over certain browser settings in order to promote a sponsored address, usually that of a fake search engine. The browser hijacker and the promoted fake engine could be monitoring the user's browsing activities and then selling the data to third parties.
In short, if you are seeing the 'Expecting value line 1 column 1 (char 0)' error, you are strongly encouraged to scan your computer system with a reputable anti-malware product. Immediately remove any detected threats.