NetCommunity does not use the explicitly defined expiration date on the membership category in the Raiser's Edge. Instead, NetCommunity calculates the expiration date based on the New Memberships Expire After <x> <intervals> setting below this, even though these values are greyed out when Specific Date is selected.

When the Expire After is set to <blank> Year(s) for these Membership Categories, NetCommunity assumes that the expiration date for the current membership transaction is 0 Years from today, which is today, hence the error. The following needs to occur:
  1. Log in to The Raiser's Edge
  2. Click Config > Membership Categories
  3. Open the Membership Category
  4. Click the Default Settings tab
  5. Change the value for Default 'Expires' To to a value other than Specific date. (Ex. Beginning of month)
  6. Set the New Memberships Expire After (and renew and rejoin if those options will be available on the web) to the maximum time frame you wish to allow users to pay their pledges. For example: If this is set to 6 months, NetCommunity will not allow a user to schedule pledge payments more than 6 months beyond their transaction date.
  7. Change Default 'Expires' To back to Specific Date
  8. Click Save and Close
  9. Log in to the NetCommunity website
  10. Navigate to the page with the membership form on it 
  11. Click edit for the Membership Form 
  12. Click Save
If the error is still occurring after following all of the steps above, remove the membership category from the membership form and then add the membership category back.