UTY8721 Error attempting to <string> file <file name>, return code is <integer>.
There was an I/O error on the specified file with the specified return code.
If possible, make the necessary corrections and resubmit the program.
Substitutions are more extensive for this message than they are for others. The values for <string>, for example, can be any of the following: + Checkpoint + Close + Open + Read + Reposition + Write referring to the intended action. The second variable, <file name>, is simply the name of the file affected. Replacing <integer> is a transaction code, defined as follows: Note that messages 1784 and 1785 above are received if a disk file is treated as tape.