Sometimes using Data | Text to Columns does not function properly depending on the type of data, how the line breaks were created, etc.
Open Your Excel Document.
Create 4-5 blank columns to the right of the column you want to split out into multiple columns. These are needed because the data from your multiple line cell will be inserted into these fields. If you do not insert these fields the data in the fields to the right of your primary cell will be overwritten.
Click on View | Macros | View Macros
Type SplitText into Macro Name field.
Sub splitText()
'splits Text active cell using ALT+10 char as separator
Dim splitVals As Variant
Dim totalVals As Long
Dim i As Integer
For i = 1 To 1000
splitVals = Split(ActiveCell.Value, Chr(10))
totalVals = UBound(splitVals)
Range(Cells(ActiveCell.Row, ActiveCell.Column + 1), Cells(ActiveCell.Row, ActiveCell.Column + 1 + totalVals)).Value = splitVals
ActiveCell.Offset(1, 0).Activate
Next i
End Sub
Click the Create button
Highlight all the text in the VBA editor and delete it. Be careful not to delete other macros you've created.
Close the VBA editor once you have pasted the code.
To run the macro highlight the first cell that you want to split the data on and Click View | Macros | View Macro then click on SplitText in your macro list and click Run. This macro does the first 1000 lines, just repeat the process on the 1001 record by highlighting it and running the macro again.