Please note that this article refers to the old Salesforce integration for GetAccept. The new one is available here: https://appexchange.salesforce.com/appxListingDetail?listingId=a0N3A00000E1Z2sUAF
Click Setup from the top header or by clicking your name and then selecting Setup from the dropdown menu.
2) Type "sites" in the quick search or manually navigate through the setup menu to Develop and then Sites.
3) Register an available force.com domain if there is no previously configured domain for your Salesforce organization.
4) Create a new Site by clicking New
5) Suggested values for Site Label and Site Name is GetAccept or similar.
6) Active checkbox should be checked
7) Active Site Home Page should be set to FileNotFound or Unauthorized
8) Checkbox Require Secure Connections (HTTPS) should be checked
See image below for sample configuration:
9) Click Save to create the new Site.
10) Click the Site Label of your new Site to show additional settings for it.
11) Click Public Access Settings
12) Click Edit.
13) Scroll down to the Custom Object Permissions section and select at least Read and Edit permissions for the GetAccept Documents-object.
14) Click Save to apply your changes.
15) Scroll down to the Enabled Apex Class Access related list and select Edit
16) Find "gaff.GetAcceptCallbackAPI" in the Available Apex Classes section. Select it and move it over to the Enabled Apex Classes section.
17) Click Save.
18) Go back to Sites (Step 1 and 2 or navigate to Setup -> App Setup -> Develop -> Sites).
19) Copy or make note of the "Site URL" for your GetAccept Callbacks Site.
20) Next, use the quick search field and type "custom settings" or manually navigate to (Setup -> App Setup -> Develop -> Custom Settings).
21) Find the "GetAcceptSettings" custom setting and click Manage.
22) Click New to add a new "Default Organization Level Value."
23) Paste in your "Site URL" and make sure to check "Enable Callbacks" checkbox. (It is strongly recommended to use "https" for the Callback Site URL).
24) Click Save.
25) All done! Your Salesforce organization is now ready to receive callbacks on status
updates from GetAccept.