Powershell excel script failure

Hi all

I have written a powershell script that creates a workbook in preparation for a ssis data load. The script runs fine on my laptop but on the server it seems to fail almost everytime stating cannot find .add on excel com object. Any help would be hugely appreciated!

# Start of Script 
## 
# Then we create and save a sample worksheet 
# Create Excel object 
$excel = new-object -comobject Excel.Application 

# Make Excel visible 
$excel.visible = $true 

# Create a new workbook 
$workbook = $excel.workbooks.add() 

# The default workbook has three sheets, remove 2 
$S2 = $workbook.sheets | where {$_.name -eq "Sheet2"} 
$s3 = $workbook.sheets | where {$_.name -eq "Sheet3"} 
#$s2.delete() 
$s3.delete() 
# Get sheet and update sheet name 
$s1 = $workbook.sheets | where {$_.name -eq 'Sheet1'} 
$s1.name = "Claims" 

# Get sheet and update sheet name 
$s2 = $workbook.sheets | where {$_.name -eq 'Sheet2'} 
$s2.name = "History"   

# Update workook properties 
$workbook.author = "Chill Winston" 
$workbook.title = "Excel and PowerShell play nice!" 
$workbook.subject = "Demonstrating the Power of PowerShell with Excel" 

# Next update some cells in the worksheet 'PowerShell Sample' 
$s1.range("A1:R1").Interior.ColorIndex = 11
$s1.range("A1:R1").Font.ColorIndex = 2
$s1.range("A1:R1").Font.Bold = $True

# Add column headers
$s1.Cells.Item(1,1) = "NUMBER" 
$s1.Cells.Item(1,2) = "NUMBER2" 
$s1.Cells.Item(1,3) = "START_DATE" 
$s1.Cells.Item(1,4) = "TERMINATION_DATE" 
$s1.Cells.Item(1,5) = "PARTICIPANT_CONSENT_OBTAINED" 
$s1.Cells.Item(1,6) = "WEEKLY_HOURS" 
$s1.Cells.Item(1,7) = "EMPLOYER_NAME" 
$s1.Cells.Item(1,8) = "EMPLOYER_STREET_1" 
$s1.Cells.Item(1,9) = "EMPLOYER_STREET_2" 
$s1.Cells.Item(1,10) = "STREET_3" 
$s1.Cells.Item(1,11) = "EMPLOYER_CITY" 
$s1.Cells.Item(1,12) = "COUNTY" 
$s1.Cells.Item(1,13) = "EMPLOYER_ZIP" 
$s1.Cells.Item(1,14) = "COUNTRY" 
$s1.Cells.Item(1,15) = "EMPLOYER_CONTACT_NAME" 
$s1.Cells.Item(1,16) = "EMPLOYER_CONTACT_MOBILE" 
$s1.Cells.Item(1,17) = "EMPLOYER_CONTACT_EMAIL" 
$s1.Cells.Item(1,18) = "EMPLOYER_CONTACT_PHONE" 


# And save it away: 
$s1.saveas("C:\Users\ChillWinston\Desktop\ProviderEvidence.xlsx") 

# close the worksheets
$excel.workbooks.close()
$excel.quit()

# end of script