If you are installing TM1 10.1 or TM1 10.1.1 the you will probably be asking your IT department to make sure they install the pre-requisites on the server.
You will find them here:
Note how it asks for "Microsoft Visual C++ 2005 SP1 Redistributable Package"
The IT department seeing TM1 is 64 bit will probably only install the 64 bit version of the package. I have even seen them install not the SP1 version. The problem will come that if they don't install the x86 version and TM1 perspectives gets installed you will receive the error Run-time error '53':File not found: tm1xl.ocx when you open perspectives.
Obviously the fix is to install the x86 version of the C++ but hopefully this post will stop many back and forth emails between you and IT