When trying to generate any invoice or report with output set as Viewer in ArchiOffice/EngineerOffice 20xx, user is prompted for a server login requiring a User ID and Password.
Follow these steps to resolve the issue:
1. Launch the Internet Information Services (IIS) manager.
2. Locate the "aspnet_client" folder under the Default Web Site and select it.
3. On the right panel, click the Authentication option under IIS.
4. Set Anonymous Authentication to Enabled; all others to Disabled.
5. Repeat the above steps in the same way with the "crystalreportviewers12" folder, if present.