How to add a border line automatically?

Hui and welcome to the forum

Have you tried using/looking into using Conditional Formatting?

I highlighted column B and typed this formaula in new formatting rule under conditional formatting

=$B:$B <>""

But is it is not working not even for B column. I want the border to continue horizontally

If you can show me a sample of what you are working with (no sensitive info), along with what your desired outcome would be, we can see what we can do?
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OK so you want a line under row 12, 24, 36 etc?

If that's the case, try this...

1. highlight the range you want to apply the conditional formatting to (A5:AV90)
2. on the home tab, styles, select CF
3. select new rule, select use formula
4. enter =MONTH($C5)=12 format border select bottom line

Originally Posted by FDibbins

OK so you want a line under row 12, 24, 36 etc?

If that's the case, try this...

1. highlight the range you want to apply the conditional formatting to (A5:AV90)
2. on the home tab, styles, select CF
3. select new rule, select use formula
4. enter =MONTH($C5)=12 format border select bottom line

Thanks

When I go to Home, there is no styles option beneath it. I am using Excel 2007 by the way

so am I, when you select HOME on the ribbon, its the 5th tab along...clipboard/font/alignment/number/STYLES