Shared resources should not be used for locking as it increases the chance of deadlocks. Any other thread could acquire (or attempt to acquire) the same lock for another unrelated purpose.

Instead, a dedicated object instance should be used for each shared resource, to avoid deadlocks or lock contention.

The following objects are considered as shared resources:

• Me
• a Type object
• a string literal
• a string instance

Noncompliant Code Example

Public Sub MyLockingMethod()
    SyncLock Me 'Noncompliant
        ' ...
    End SyncLock
End Sub

Compliant Solution

Class MyClass
    Dim lockObj As New Object()

    Public Sub MyLockingMethod()
        SyncLock lockObj
            ' ...
        End SyncLock
    End Sub
End Class

See

Microsoft Documentation: Managed Threading Best Practices