When processing *.xlsx and *.xlsm, cell comments are missing after a file manipulation using some of the file instructions.
Why does this happen?
There is a technical limitation in the underlying components for manipultating excel data thats prevents comment data from being correctly parsed, and restained, for some instruction. The best work around for this problem at the moment is to convert file concered into *.xls format.
How to fix this
The current work around for this problem is to convert the file concerned into the older *.xls format – and continue working with the file in this format.