The “PHP Warning: fread(): Length parameter must be greater than 0” error message is typically thrown when the fread() function in PHP is passed an argument of zero or a negative number as the length of data to be read from a file. The fread() function expects a positive integer as the length parameter, and a value of zero or a negative number is not a valid argument.
To resolve this error, you need to modify the code that calls the fread() function to ensure that a positive integer is passed as the length parameter. The exact solution will depend on the specifics of the code in question, but it might involve checking the return value of another function that provides the length parameter, or adding additional error checking to ensure that the length parameter is not negative.
It is recommended to thoroughly test the code after making any changes to ensure that the error has been resolved, and that the code is functioning as expected.