excel - solver function

[schedule-r]

Here's an excel question:
When using the solver tool, how do you lock cells from changing.  I have a model where the sover is helping me make a work schedule.  I am using the solver to vary a range of cells until the schedule "solves" iself (specifically a binary integer linear program).
Here's my question:  
      The solver does its work by changing a range of cells; however, there are a few cells in here that I NEED to take the value that I want.  Dollar signs do not seem to do the trick.  I have a very small working knowledge of excel, and there may be a very simple remedy to this problem.  If you can help or point me in a direction where I can find an answer, it would make my next few evenings easier.  

Thanks!

[soybean]

I've been an Excel user for years, but I've never used this tool.  Here's a Microsoft reference: Introduction to optimization with the Excel Solver tool.  I don't know whether it answers your question.  A Google search on Excel Solver will yield numerous other references.