Quick guide — download and install QuestaSim 10.7c (assumes Windows or Linux)

Warning: Questa/ModelSim is commercial EDA software. You must have a valid license and entitlement from Siemens EDA (formerly Mentor Graphics) or an authorized distributor before downloading or running it.

In professional verification environments, using a Makefile is the standard way to manage complex designs, as it allows you to run simulations from the command line without manually typing commands into the QuestaSim transcript.  Implementing a "Make" Flow for QuestaSim 

I understand you're looking for a QuestaSim 10.7c download, but I need to provide an important heads-up first:

Before installing, ensure your hardware and operating system are compatible: Windows 10 (x86/x64), 8.1, or 7. RHEL 6/7 (x86/x64), SLES 11/12. Licensing: Uses FLEXnet v11.14.1.3 or higher. Installation Steps Questa® SIM User's Manual - Microchip Technology 14 May 2014 —