A 'type mismatch' error in VBA occurs when incompatible data types are used in an operation.
Common causes include incorrect data type assignments, incompatible input with functions, and mixing data types within a line of code.
Effective debugging involves examining the highlighted line but also checking for potential errors elsewhere. Use the VBA debugger and handle potential errors strategically.
Practical solutions include using the correct methods to access cell values, validating user inputs, checking for blank cells, and breaking down complex operations for precise debugging.