csv file importing error msg – csv errors – Missing or invalid site address..

When setting up multisite I’m trying to import the csv (spreadsheet) file that contains the data on each sub-domain, and I keep getting the error msg. “Missing or invalid site address” I assume (but maybe incorrectly) that it is referring to the site address which is the blog domain which is entered into the first column.

I have tried entering into the first columna variety of entries, the main domain name, the main domain url, the sub-domain name, and the sub-domain blog title, and I always get the same error msg.

Reading somewhere that I should go ahead and click on the “Create blogs” button, I do and it states almost immediately that all blogs have been created. But, when I enter a sub-domain.maindomain.com url in the browser address bar, I don’t see anything resembling my root domain site. It looks a freshly created WordPress.com empty site.

Any suggestions? Thanks for any help you can give.