9sBlog

Daniel Miller

Daniel spent five years as an IT support specialist, walking colleagues through Windows, Office, printers and file problems before moving into tech writing. He covers the desktop side of 9sBlog: Windows 10 and 11, Microsoft Office, PDFs and the everyday software fixes that used to land on his support desk.

121 articles

A person working at a desk with a laptop and a wristwatch
Software

How to Do a Mail Merge in Word

Send personalized letters or emails from one document. This mail merge guide covers the Mailings tab wizard, an Excel list, merge fields, and formatting fixes.

3 min read
A tidy office desk workspace with a laptop and supplies
PC

Fix 100% Disk Usage on Windows 11

Windows 11 stuck at 100% disk usage? Find the process in Task Manager, then calm SysMain, Windows Search, and the few known culprits to get speed back.

4 min read
A person typing at a computer in a workspace
PC

Fix a Black Screen on Windows 11

A black screen on Windows 11 comes in two forms: before sign-in and after. Here is how to wake the display, restart Explorer, and boot Safe Mode to fix it.

3 min read
An open planner and calendar on a desk for organizing tasks
Software

How to Insert a Checkbox in Excel

Excel now has a real cell checkbox that returns TRUE or FALSE. Here is how to add it in Microsoft 365, plus the classic Developer method for older versions.

3 min read
A MacBook laptop on a desk
Software

How to Clear Cookies in Firefox

Clear cookies in Firefox for one site or all sites using the address-bar lock icon or Privacy & Security settings, on desktop or Android.

3 min read