In order to verify your file with BriteVerify, you will need to have your email list saved as either a .txt or .csv file. Even if you have already received your file as a .csv, we strongly recommend opening the file in Excel and re-exporting as a .csv to make sure that it is done correctly.
NOTE: Renaming the file's extension to ".csv" will not actually do anything, you must actually export from Excel as a csv file to change the file type.
Once your file is open in Excel, go to FILE > SAVE AS to bring up the "Save As" dialog window, shown below.
Select "Comma Separated (.csv)" from the Format drop-down menu and save your file.
A warning message will appear as you save your file, this is normal and will not affect your file in any way. Just press "Continue" and move on with your life.
Congratulations, you are now the proud owner of a properly formatted data file, which is a pretty awesome thing to have. Now go get that sucker verified and start sending some emails!