After purchasing DocFetcher Server with a particular client limit, you have the option to upgrade to a higher client limit. — Downgrading to a lower client limit is not possible.

In order to upgrade, you need to buy DocFetcher Server anew at the desired higher client limit, then send an email to Support to request a refund of your previous lower-client-limit purchase. IMPORTANT:

• To get a refund, you must make the new purchase with the same Gumroad account with which you made the previous purchase.
• To get a refund, you must also make the new purchase for the same OS as before, e.g., if you bought DocFetcher Server for Windows before, then you can only upgrade by buying DocFetcher Server for Windows again, at a higher client limit. Double-check that you’re not accidentally re-purchasing DocFetcher Server for the wrong OS.
• And as was already noted: To get a refund, you must make the new purchase at a higher client limit than before.

There’s no need to send a lengthy email to Support, just put “Client limit upgrade” in the email subject field, and put the email address of the Gumroad account to be refunded in the email body, if that email address is different from the email address from which you’re sending the email.

If the above conditions are met, then you will get a refund. But if you’re unsure, feel free to ask Support for confirmation before making the new purchase.

If you’re wondering why there isn’t a less convoluted way to upgrade, that’s because the Gumroad distribution platform on which DocFetcher Server is sold currently doesn’t offer a direct method to upgrade between product versions.