Hi Ben,
Thank you for posting in Windows Server Forum.
Initially suggest you to update RDP 8.1 which will work better for this scenario.
Yes, there is a way to reduce the number of password prompt, here you need to enable RD Web Access Single Sign-On (SSO), where the password will be saved and need to enter the credential for single time.
There are certain requirements for this feature, as follow.
• To take advantage of the new Web SSO feature, the client must be running Remote Desktop Connection (RDC) 7.0.
• In order for Web SSO to work:
1. The connection in RemoteApp and Desktop Connections must have an ID. By default, it is set to the Fully Qualified Domain Name (FQDN) of the RD Connection Broker server in case of RD Connection Broker mode. In RD Session mode, it is set to the FQDN of the
RD Web Access server.
2. RemoteApp programs must be digitally signed using a Server Authentication certificate [Secure Sockets Layer (SSL) certificate]. The certificate Enhanced Key Usage section must contain ‘Server Authentication (1.3.6.1.5.5.7.3.1)’. More details about the types
of certificates used to digitally sign RemoteApp programs can be found here.
3. Client operating systems must trust the certificate with which the RemoteApp programs are signed.
More information.
Introducing Web Single Sign-On for RemoteApp and Desktop Connections
http://blogs.msdn.com/b/rds/archive/2009/08/11/introducing-web-single-sign-on-for-remoteapp-and-desktop-connections.aspx
Remote Desktop Web Access single sign-on now easier to enable in Windows Server 2012
http://blogs.msdn.com/b/rds/archive/2012/06/25/remote-desktop-web-access-single-sign-on-now-easier-to-enable-in-windows-server-2012.aspx
Hope it helps!
Thanks.
Dharmesh Solanki
TechNet Community Support
