In this presentation, Excel expert David Ringstrom, CPA, shows you how to implement internal control features within your Excel spreadsheets. He explains how several Excel features—Data Validation, Conditional Formatting, and hide and protect features—can be implemented to control users’ actions and protect your worksheets and workbooks from unauthorized changes. In addition, David explains the benefits of the VLOOKUP, SUMIF, and CELL functions.

David demonstrates every technique at least twice: first, on a PowerPoint slide with numbered steps, and second, in Excel 2016. He draws your attention to any differences in Excel 2013, 2010, or 2007 during the presentation as well as in his detailed handouts. David also provides an Excel workbook that includes most of the examples he uses during the webcast.  

Topics Covered:

  • Toggling the Locked status of a worksheet cell on or off by way of a custom shortcut.
  • Utilizing Data Validation to limit percentages entered in a cell to a specific range of values.
  • Creating an in-cell list by way of Excel’s Data Validation feature.
  • Using a custom number format to hide zero amounts within a specific area of a spreadsheet.
  • Using Conditional Formatting to identify unlocked cells into which data can be entered. 
  • Improving the integrity of spreadsheets with Excel’s VLOOKUP function.
  • Using Data Validation to create a rule that ensures dates entered within a cell are greater than or equal to today’s date.
  • Ensuring proper VLOOKUP integrity by using Data Validation to create an in-cell drop-down list.
  • Using Conditional Formatting to color-code your data, identify duplicates, and apply icons.
  • Overcoming VLOOKUP’s quirks by using SUMIF to look up numeric values.
  • Using Excel’s VLOOKUP function to look up an item description based on an input provided by the user.
  • Preserving key formulas using hide and protect features.
Learning Objectives
  • Recognize which ribbon tab contains the Data Validation feature.
  • Identify which input is valid for a data validation rule limiting inputs to whole numbers between 0 and 100.
  • Recognize the ribbon tab the Table feature appears within.
Last updated/reviewed: March 4, 2024

Included In Certifications

This course is included in the following Certification Programs:

17 CoursesExcel Modeler Certification

  1. Excel Efficiency: VLOOKUP
  2. Excel Efficiency: Logic Functions
  3. Excel Efficiency: Filtering and Formatting Data
  4. Excel Efficiency: Intermediate Pivot Tables
  5. Excel Efficiency: Auditing Spreadsheets
  6. Excel Efficiency: Minimizing Worksheet Errors
  7. Excel Efficiency: Workbook Links
  8. Excel Efficiency: What-If Analysis in Microsoft Excel
  9. Excel Efficiency: Quick and Easy Financial Statements in Excel
  10. Excel Efficiency: Budget Spreadsheets
  11. Hands-On Excel: Waterfall Calculations
  12. Excel Efficiency: Table Feature
  13. Excel Efficiency: Intro to Macros Part 1
  14. Excel Efficiency: Intro to Macros Part 2
  15. Excel Efficiency: Excel Chart Speed Tips
  16. Excel Efficiency: Taming Large Spreadsheets
  17. Excel Efficiency: Internal Controls
6 Reviews (38 ratings)


Anonymous Author
Instructor did a great job at explaining the various uses of Data Validation, Conditional Formatting, VLOOKUP and SUMIF. I found most interesting the audit function for seeing which cells in the worksheet were unlocked as well as seeing if a user overrode the data validation cells. Appreciate the inclusion of going over the PowerPoint slides before demonstrating on Excel.

Anonymous Author
David is a very good instructor. I normally look for courses that he offers as he is very knowledgeable in excel and I learned a lot from his courses. His way of teaching is very effective.

Member's Profile
This course was very helpful. new tools for me to practice and master. If you work with data and excel this is the right course. take it and you will find that worth more than you imagine.

Member's Profile
David Ringstrom is an excellent teacher for Excel. He is easy to understand and provides examples that are relevant and easy to follow. Another great course by him.

Anonymous Author
Wow, so much information and so many tips packed into one lesson! Save the slides; these are very beneficial during and after the course!

Anonymous Author
Great content with examples - learned something new!

Course Complexity:

Program Prerequisites: Previous Experience with Excel Spreadsheets

Advance Preparation: None

Education Provider Information
Company: Illumeo, Inc., 75 East Santa Clara St., Suite 1215, San Jose, CA 95113
Contact: For more information regarding this course, including complaint and cancellation policies, please contact our offices at (408) 400- 3993 or send an e-mail to .
Instructor for this course
Course Syllabus
  Introduction & Goals to Internal Control 6:30
  Data Validation for Data Fields6:21
  Using Data Validation for Percentages5:18
  Using Data Validation for Whole Numbers7:49
  Naming Tables and Cell Ranges8:26
  Using VLOOKUP to Return Item Descriptions6:34
  Empty Cells Cause VLOOKUP to Return #N/A7:05
  Data Validation for Item List9:06
  Making Unit Price Field Appear Empty7:24
  Future-Proofing SUM Function6:14
  Lock/Unlock Cell Toolbar Icon8:33
  Hiding Worksheet Formulas7:57
  Allow Certain Users to Override Prices7:16
  Identify Overwritten Data Validation 5:56
  Excel Efficiency - Internal Control1:40:29
  Slides: Excel Efficiency: Internal ControlsPDF
  Excel Efficiency: Internal Controls Glossary/IndexPDF
  Workbook: Excel Efficiency: Internal Control XLSX