STAF' s bitness should match TestComplete's bitness.

STAF is the underlying communication layer for SAFS, normally we will install 32-bit STAF on 32-bit machine, and 64-bit STAF on 64-bit machine.

But recently, we met some problem running SAFS-TestComplete on Windows 10 (64-bit system).
================== quoted from TestComplete 32 64 bits =========================================================
By default, TestComplete is installed into the C:/Program Files (x86)/SmartBear/TestComplete 14 folder. (Note x86 in the path.) The 64-bit executable is placed in the /x64/Bin subfolder of this folder, that is, in Program Files (x86)/SmartBear/TestComplete 14/x64/Bin. The 32-bit version is located in the Program Files (x86)/SmartBear/TestComplete 14/Bin folder as it was before.
===================================================================================================

We are using C:/Program Files (x86)/SmartBear/TestComplete 14/Bin/TestComplete.exe to start the TestComplete, so it is 32-bit executable, but "Windows 10" is 64 bit system, so the installed STAF is also 64 bit. I re-installed the 32-bit STAF and the problem is gone and SASF-TC can work normally.

In conclusion, we need to use the matched STAF for TestComplete:
1. 32-bit STAF for C:/Program Files (x86)/SmartBear/TestComplete 14/Bin/
2. 64-bit STAF for C:/Program Files (x86)/SmartBear/TestComplete 14/x64/Bin/