I deleted entire 45th row, now numbering series gone wrong.

See if this helps :

How to number rows after inserting or deleting rows automatically in Excel?

Look at comments of that page, "if i delete the row, is there any possibility to set below numbers are in serial". They are still posting questions means your link didn't help me.

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By slightly editing the posted macro, you can achieve the goal you desire :

The above is designed to delete one row at a time and still maintain the
correct numbering in your column. Your original post indicated you are
deleting one row at a time.

It has been a pleasure helping you. Stay healthy !

Where should I enter this code? How to activate it?

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Paste the code in the Sheet module, of the sheet you want it applied to.

It functions automatically when a row is deleted. You won't have to do anything.

This line in the code : For I = 1 To 50 can be changed if you want the number
of affected rows changed. For example, if you want it applied to 100 rows, change the
50 to 100. If want it applied to just the first 20 rows, change the 50 to 20.

should I copy your code in this sheet module?:





If not, show me correct sheet module.

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If that is the Sheet that you want the macro code to work on. Yes

Why I am getting this error while I am saving your code?

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You need to save the workbook as macro-enabled.

Click NO, then in the small window that opens ... choose File Type as .XLSM

Yes I saved my file as XLSM, saved your code in my worksheet, still numbering series didn't change:






still its showing 46 instead of 45.

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Can you post your workbook ?

Disregard posting your workbook.

Let's try a formula instead of the macro.

If you don't have a header in A1, paste the following formula in A1. If you do have a
header, then paste the formula in A2.

If A1 : =IF(ISBLANK(B1)," ",COUNTA($B$1:B1))

If A2 : =IF(ISBLANK(B2)," ",COUNTA($B$2:B2))

Once you have the formula in the cell, click on the cell and a small dot will appear
in the lower right hand corner of the cell. Hover your cursor over that tiny black
dot until the cursor becomes a cross symbol. While it remains the cross, double
click the dot. The formula should auto-fill all the cells in Col A that are adjacent
to a cell in Col B that has some data.

Be sure to delete the macro from the worksheet module.

My problem is arrives at A58 but you are saying A2 & B2, I am confused.

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What Column and what starting and ending cell do you want the auto numbering to work ?