Hello @augustaarts. I'm so sorry that your contacts are not showing in the preview after selecting your file. The first thing I will suggest would be to close out of your browser and reopen it. If this doesn't work, try going into either a private or incognito window (depending on your browser) and see if the contacts will load then. If this works, this means that there is probably a plugin in your browser that is causing the page to not load properly. Here is an FAQ on how to test to see what plugin is affecting your connectivity and also how to open an incognito/private window. The last thing we would test is if it is an overall browser issue by working in a completely different browser. We recommend using Google Chrome when working in your Constant Contact account.
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