Macro runs fully in debug mode, but partially only when played

[PraRan]

Hi,
I have a simple macro to copy-paste formula over a range of active rows. I've used Dim statement to identify the last active row using worksheet countA function. And then written statements to copy formula from a specific location and paste in a specific cell for the active number of rows.

Dim LastRow as long
LastRow WorksheetFunction.CountA(Sheet1.Range("A:A")) + 2 {I need the +2 as there are blank rows at the top of the report that need to be counted in the total number of active rows}
Sheet1.activate
Range("A2:F2").Select {A2 to F2 have vlookup formula}
Selection.Copy
Range("Q5:AH" & LastRow).PasteSpecial

When I click the button to run the macro, it will run for a partial range. For example if the report is 32,500 rows long, formula will be pasted into 15,000 rows. However when I step in to debug the paste function will be applied to the entire range of 32,500 rows.

What may be going wrong?

 

[Peter_SSs]

Are you sure there are not more blank cells somewhere down column A?

What happens if you change the calculation of LastRow to this?

LastRow = Sheet1.Range("A" & Rows.Count).End(xlUp).Row

 

[diddi]

you are missing an "=" sign

LastRow  = WorksheetFunction.CountA(Sheet1.Range("A:A")) + 2

 

[Peter_SSs]

you are missing an "=" sign

I doubt that is the case in the OP's workbook since they report that the code actually runs.

 

[PraRan]

Thanks for replying Diddi and Peter_SSs. There's an = sign when defining LastRow.
What's stranger is that the code runs perfectly fine when my coworker runs it on their computer. But not on mine. On mine the code runs only partially. We have the same version of XL. I've tried stepping in and running it through debug to see where it falls apart. But the code runs fine in debug mode. It's just leaving me very baffled. So bizarre.

 

[diddi]

this might seem like an odd thought, but have you checked your hard drive. if it is highly fragmented or very full, this task which is quite hdd intensive would run when there is enough time for hdd to keep up, but not at full speed

 

[PraRan]

this might seem like an odd thought, but have you checked your hard drive. if it is highly fragmented or very full, this task which is quite hdd intensive would run when there is enough time for hdd to keep up, but not at full speed

Thanks.
Uninstall and reinstall seemed to do the trick for now. But will keep this in mind if I run into similar issue in future.