Occasionally, when importing leads from a CSV file, Open Leads users will encounter an error message, "Oops! Invalid CSV file." This is almost always triggered when importing a CSV that was created in Microsoft Excel. 

There is a known bug in Excel that may cause some problems when saving an XLS file as CSV. The solution to this problem is outlined on the  Microsoft Support website. This works most of the time to allow you to save a properly formatted file. However, the preferred solution is to use another spreadsheet application - we recommend OpenOffice from Apache OpenOffice is a free office suite, and is 100% MS Office compatible, and cleanly exports spreadsheets as CSV files. 

Simply open your corrupt CSV in OpenOffice, and the export that file as a CSV. It will then import fine into Open Leads.