Firstly, trying to run telnet on any modern Windows 2008 server will cause severe distress to say the least. Why? Because Microsoft deemed that useful little command unnecessary to be installed by default. Anyway... So you go to Programs and Features and add the Telnet Client feature.

To my mind Telnet Client is a very, very small executable. It cannot possibly have large DLL dependencies. So it was much to my dismay and horror when I realised installing this took over 4 minutes on a modern server. So much for progress...

Compare this to Ubuntu Linux:

waldo@waldopc:~$ time sudo apt-get install --reinstall telnet
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages were automatically installed and are no longer required:
  libstdc++5
Use 'apt-get autoremove' to remove them.
0 upgraded, 0 newly installed, 1 reinstalled, 0 to remove and 24 not upgraded.
Need to get 0B/72.2kB of archives.
After this operation, 0B of additional disk space will be used.
Do you want to continue [Y/n]? Y
(Reading database ... 332718 files and directories currently installed.)
Preparing to replace telnet 0.17-36build1 (using .../telnet_0.17-36build1_amd64.deb) ...
Unpacking replacement telnet ...
Processing triggers for man-db ...
Setting up telnet (0.17-36build1) ...
real    0m4.719s
user    0m0.960s
sys 0m0.180s

4 seconds vs 4 minutes???