"Visualize as " uses data of the SINGLE cell, that is exported to file and then opened in program, that you specify. It is your responsibility, that data in the cell has correct format.
Most common usage case: when files are stored in BINARY fields, you can export that file to disk and open with the associated problem (for example Sharepoint does this).
If you just want to export data to Excel from Grid you have 2 ways:
1. Use our Results Grid Scripter engine: Right-Click the Grid -> "Script Grid Data"->Script as XML Spreadsheet
2. Select all data in the Grid->Right Click->"Copy Selection as XML Spreadsheet(Excel)"