How to Add a Drop Down List in Excel That Updates Itself
Add a drop-down list in Excel with Data Validation, make it update itself from a Table, build dependent lists, and fix a dropdown that stopped working.
How-To Guides
Step-by-step guides for the software and systems people actually use at work.
How to Use VLOOKUP in Excel (And Why It Returns #N/A)
Use VLOOKUP in Excel with exact match, understand why it only looks right, fix #N/A errors, and know when XLOOKUP or INDEX MATCH is the better choice.
How to Unhide Columns in Excel (Including Column A)
Unhide columns in Excel, reveal column A when the normal method fails, and fix the cases where Unhide does nothing because they were never hidden.
How to Lock Cells in Excel (It Works Backwards)
Lock specific cells in Excel by unlocking your input cells first, then protecting the sheet — plus what sheet protection genuinely does and doesn’t do.
How to Merge Cells in Excel (And Why You Usually Shouldn’t)
Merge cells in Excel, see what merging breaks in sorting and pivots, and use Center Across Selection for the same look without the problems.
How to Remove Duplicates in Excel (Without Losing Data)
Remove duplicates in Excel, choose which columns define a match, find them safely first with UNIQUE or COUNTIF, and fix duplicates Excel cannot see.
How to Disable Startup Programs (All 4 Places They Hide)
Disable startup programs in Windows using Task Manager, the Startup folder, Task Scheduler and Services — and stop apps that re-enable themselves.
How to Speed Up Your Computer (Diagnose It First)
Find out why your Windows PC is slow using Task Manager, then apply the fix that matches the real bottleneck — memory, disk, startup or one bad process.
How to Change Screen Resolution (And When Not To)
Change screen resolution on Windows, use scaling instead when text is too small, and fix a resolution option that will not appear in the list.
How to Run Disk Cleanup (Use the Button Everyone Misses)
Run Disk Cleanup on Windows and click Clean up system files to reveal 20GB or more of previous installations, update caches and superseded files.