What is the difference between a Software Architect and a Solutions Architect?

This two species are usually found in large corporations which are highly process driven by nature... :)

In layman's terms, A Solution Architect proposes The Functional Screen that achieves some Business Constraint, A Software Architect proposes The Set of Programs ( Components ) aka Skeleton and It's intercommunication to deliver that Screen right.

Both of them make sure that the screen is implemented correctly by some "brogrammer" who has a limited vision about it !

Solutions Architect

• (S)He doesn't do the technology ( software ) design, mostly works on one level up on functional design.
• This person is also known as product manager or business analyst in other geographies.
• Solution Architect would usually have better domain expertise and good grasp on usage and limitations of technology.
• (S)He takes a holistic approach to understand the customer problems and tries to bring the best possible feature set. aka Solutions..
• (S)He is also responsible for  prioritizing the solutions that needed to be implemented.
• He writes "user stories" which narrates the actual workflow the customer is going to expect out of the final deliverable ( Software ).
• (S)He has to be friends with technology team as well, to drill down real objective in their mind which customer would be delighted to address.
• Usually Solutions Architects are required in very specialized industries where others ( technology professionals ) truly need the guidance on industry specific functionality.

Software Architect

• Here comes the smart animal, This poor guy has to learn all the functionality the Solution Architect has proposed and develop a Real Software Architecture out of it.. ( Double Work but Challenging & Satisfying )
• This person have to thin through about the possible approaches to develop the actual Application addressing the Features.
• One actually prepares an architectural design which ( software ) developers are going to refer.
• (S)He is responsible for driving the long term strategy for development of a system.
• (S)He evaluates various tools and techniques and creates a common ground on which developers work and perform daily routines.
• Architectural Design,
  Software technology Stack Selection,
  Component Build vs Buy Decisions and similar technology and implementation oriented decisions are finalized by Software Architect.

Ref:

https://www.quora.com/What-is-the-difference-between-a-Software-Architect-and-a-Solutions-Architect