How to Open Multiple CSV Files in One Excel Spreadsheet. The CSV file extension appears on text documents that contain comma-separated values. Like spreadsheet data, each line in a CSV file ...

Though DAT files, which house data as the shortened name implies, are usually best left alone, here's how you can open them.

Opening Local Files The Analyst Application supports many different file formats, including SAS data sets, Excel spreadsheets, Lotus spreadsheets, SPSS portable files, and delimited files. You can ...

If you cannot open an Excel file and see Excel cannot open the file because the file format or extension is not valid error, see this post.

If you're having trouble opening a DAT file, I'll show you a simple and free way to do it. This method works on both Mac and PC. Just open your browser and go to winmaildat.com. It's a ...