When saving a LabChart 7 for Mac or earlier data file to later open on a LabChart for Windows software (LabChart or LabChart reader), you must select the following: File -> Save as -> LabChart for Windows Data.
This saves the file in the *.adicht format. Once the file is saved in this format, you will then be able to open it in LabChart or LabChart Reader for Windows. Note: this is also the same format that is used for LabChart 8 and LabChart 8 Reader for Mac.
For further technical assistance with this or any other issue, please contact ADInstruments Technical Support by clicking HERE.