Excel – What causes Excel to raise an error about “one or more formula references” when saving

The reason is probably differing 32-bit memory fragmentation on the 2 Pcs (its often difficult to use all of the theoretically available 2 GB).
You can reduce the amount of memory used by the pivot table by reducing the number of columns and/or reducing the memory required by some of the columns (text strings are a good candidate).
(You can measure the amount of memory used by the pivot cache with VBA PivotCache.memoryUsed)
I assume you are creating the pivot cache by reading the data from the query directly into the pivot cache rather than putting the query data onto a worksheet and basing the the pivot on the worksheet, which would use much more memory.
You don't say what the >1000000 formulas are so I don't have any suggestions for improvement for them.
If you want to use large amounts of data in Excel pivots etc you would get better results from the 64-bit version of Excel 2010 which does not have the 2-GB limit

You can do this for a range by:

1. selecting the range.
2. Click the arrow next to the button that appears.
3. Select ignore error

Opton 2 via vba: select your cells and run the following macro

Sub Example() 

    Dim rngCell As Range, bError As Byte 
    For Each rngCell In Selection.Cells 

        For bError = 1 To 7 Step 1 

            With rngCell 
                If .Errors(bError).Value Then 
                    .Errors(bError).Ignore = True
                End If 
            End With         
        Next bError     
    Next rngCell 

End Sub