Drive redirection error

Hi,

I'm having issues with drive redirection on some of my servers.
I can browse the file system on my Mac just fine but when initiating a transfer it stalls the connection for almost half a minute and eventually errors out.
When I then go back to the redirected drive, I get another error and have to reconnect to gain access again.
See the attachments for both error messages.

Most of the time, I'm seeing this on servers that are outside my LAN (they are in fact EC2 instances) and transfering files larger than around 2MB.
When doing the same thing on servers that are inside my LAN the transfers are working most of the time but I can't do anything else while they are in progress. The connection basically freezes and resumes only after the transfer is complete. Obviously this is a major PITA when transferring large files.
Everything works fine for very small files, both on my LAN and WAN.

My LAN connection is 1Gbit and my WAN connection is 70Mbit.
The EC2 instances are freshly set up t2.micro Win2k12 R2 machines and I'm not having the issue with mstsc or MSRDP for Mac from the same machine.

Any ideas?
edited by unprofessionals on 5/19/2015
edited by unprofessionals on 5/19/2015