error C3646 SharedDataLock unknown override specifier

The error message "error C3646: 'SharedDataLock': unknown override specifier" usually occurs when you try to use an unknown or invalid override specifier in your code.

To fix this error, you need to make sure that you are using a valid override specifier for the declaration of the 'SharedDataLock' class or member. The valid override specifiers in C++ are 'override' and 'final'.

Here's an example of how to use the 'override' specifier correctly:

class BaseClass {
public:
    virtual void foo() {}
};

class DerivedClass : public BaseClass {
public:
    void foo() override {}
};

In this example, the 'foo' function in the 'DerivedClass' is correctly declared with the 'override' specifier, indicating that it is intended to override the base class function.

Make sure to review your code and check for any incorrect or misspelled override specifiers, and correct them accordingly