When trying to import or export a file I am receiving an "I/O" error. The message may have 103 (as shown below) or other numbers.
I/O error means input/output error and this occurs because the selected file you are trying to import/export is open elsewhere and cannot be read/written to at the same time by another program.
To resolve this error close the file you are trying to import and the program with which the file is opened.
For example: if you are trying to import a CSV file and this error occurs it means you have the CSV file open outside of the cashbook program. You need to close the CSV file and try to import it again.
If all else fails, try restarting Stockbook, or restart the computer and try Stockbook again.