Link to export: Make excel-fil and import 
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Select the the Company Module
Select the tab Import / Export
Click on "Import/ update Companies. Review Exporting data to MS-Excel to Create Excel-file for import and update to better understand how to prepare an excel file from dRofus that could be used in this process.
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5. Select which sheet in your excel fil that you will export information from
6. Select Row
7. Select if you wouldeither to:
Update existing contact
Import new
Import and Update
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9. Enter the letter to the coloum in your excelfil the excel file that you would like to import
Read more about excel-import underIntroduction: Import/update with Excel-file
10. Select import