Comment 6 for bug 944040

--- Overview ---
I installed Precise Beta 2 (updated to most current packages as of 4/19/12) and I've been running into the same issue as described in the initial bug report. I was getting the 'Unable to connect to RDP server XXXXXX' error dialog when trying to connect my saved RDP entries. Remmina was also displaying the following messages on the command line:

   SSL_write: Failure in SSL library (protocol error?)
   Authentication failure, check credentials.
   If credentials are valid, the NTLMSSP implementation may be to blame.

Jim R. also reports not being able to connect to RDP using a hostname/FQDN, but from my testing that is a second issue and should be filed in a separate bug report. I'll explain the both problems below.

For reference, Remmina package version I am testing with is: 1.0.0-1ubuntu5.

--- Problem #1 ('Unable to connect to RDP server XXXXXX') ---

For this problem I should note that I transfered my ~/.remmina directory from my previous Ubuntu 11.10 installation to the fresh installation of Precise Beta 2 since I had a lot of RDP entries defined. This caused a problem because Remmina can apparently store passwords for RDP entries in one of two locations: in the same file where the RDP information is stored (~/.remmina/<specific-entry>.remmina) or in the gnome keyring. Apparently in Ubuntu 11.10, the passwords for my RDP entries were being stored in the gnome keyring, but in Precise Beta 2 the package 'remmina-plugin-gnome' which gives remmina the ability to work with the gnome keyring is not installed by default. Therefore, it wasn't able to pull my password out of the keyring and failed to connect to the RDP server.

Problem #1 Workaround: Install 'remmina-plugin-gnome' and/or edit each of your RDP entries and re-enter the password. If 'remmina-plugin-gnome' is not installed, when you re-enter a password, it will get saved in ~/.remmina instead of the gnome keyring.

To the Ubuntu package maintainer: Would it be a good idea to define the 'remmina-plugin-gnome' package as a dependency of either the 'remmina' or 'remmina-plugin-rdp' packages, so that it is installed automatically (I'm not quite sure which package it should be a dependency of since I don't know if other remmina plugins besides the rdp one can use the gnome keyring functionality)?

--- Problem #2 (Unable to connect to RDP session via a hostname or FQDN) ---

I'm not sure if this is the exact same thing Jim R. is seeing, but RDP sessions can connect with an IP address, but there are problems when trying to use a hostname or FQDN on Precise (not sure if this also happens with vnc, nx, etc). When trying to use a hostname or FQDN, I will sometimes see the following dialog box message without any progress for a while:

   Connecting to 'XXXXXX' ...

At first, I thought Remmina would stay on this dialog box and never connect but then I decided to wait a little longer and it eventually connects after about 120-130 seconds and asks me to accept a certificate. For some hosts I see this delay, but for other hosts the RDP session connects immediately and I don't get asked to accept a certificate. After a little troubleshooting, it looks like this is related to ipv6. After I disabled ipv6 in Ubuntu, I was able to immediately connect with RDP to any host using a hostname or FQDN.

Problem #2 Workaround: Disable ipv6 in ubuntu. This is the way I did it...Create the file '/etc/sysctl.d/10-ipv6-disable' and add the following contents to the file then reboot:

   net.ipv6.conf.all.disable_ipv6 = 1
   net.ipv6.conf.default.disable_ipv6 = 1
   net.ipv6.conf.lo.disable_ipv6 = 1