'utf-8' codec can't decode byte 0xd4 in position 2: invalid continuation byte

This error message usually occurs when a program is trying to decode a string using the 'utf-8' codec, but encounters a byte that is not a valid continuation byte.

In UTF-8 encoding, a character can be represented by 1 to 4 bytes. The first byte of a multi-byte sequence starts with a set of bits that indicates how many bytes are used to represent the character. The following bytes in the sequence all start with the bit pattern '10' to indicate that they are continuation bytes.

If a byte is encountered that does not start with '10' when decoding a string, it means that it is not a valid continuation byte and cannot be decoded. This can happen if the string was not properly encoded in UTF-8 or if there was a transmission error that corrupted the data.

To fix this error, you may need to check the source of the string to ensure that it is properly encoded in UTF-8. You may also need to check for any data transmission errors that may have caused the corruption of the data.