Format your columns in Excel accordingly. It looks like if you format the cell in Excel as text it will keep a leading zero.

When I export a Thunderbird address book how can I pre-format the Excel column into which the csv file is delivered ?

Is this about leading zeroes in phone numbers? That has bitten me in the past too, but I don't recall the workaround. I suspect that formats with embedded spaces, or international dialling codes (e.g. +44), or brackets round area codes will cause the data to be treated as text, not numerics.

It may be necessary to export to csv, rename the file as a text file and then import it (or copy-and-paste using a text editor) into Excel. The data import wizard, or the text-to-columns converter will let you specify which columns to import and how to format them. As mentioned, selecting "text" type will preserve leading zeroes.

One wonders why Thunderbird doesn't wrap phone numbers in quotes: "0800 123 456" thus forcing them to be treated as text.

Zenos, thank you for the most enlightening response so far - but I cannot get the TB csv export option to work with MS or OpenOffice.

The juice is not worth the crush now.

I just tried it here with TB31, LibreOffice Calc LMDE and it invited me to import the CSV file, allowing me to specify the type of data. But even without my setting it to "Text" for the phone numbers, they appeared to import as text anyway, with leading zeroes intact.

LibreOffice Calc LMDE offers hope.

OpenOffice also allows eg the mobile numbers to be specified as text but then requires saving as ODS and then how to convert to CSV ?

Excel 2007 : perhaps this too has a way of invoking the specify the type of data option ?

Thank you Zanos.

Try this: Open MS Excel 2007 click on 'Data' tab click on 'Get External Data' and choose 'From Text' Import Text file window opens select the saved .csv file and click on 'import'

Text Import wizard step 1 of 3 opens select 'delimited'

these should be auto selected start import at row 1 file origin: windows (ANSI)

click on 'Next'

step 2 of 3 select 'Tab' select 'comma' this should make the data preview shiow as columns with correct column name. Click on 'Next'

step 3 of 3

From 'Data Preview Area' select all

the columns which you would want to be displayed as text. Once selected the background will be black and the text will be white. This allows you to select columns and set the type of data format Suggest you highlight/select the eg: Work Phone and Home Phone columns. Then on the same window from the group 'Column Data format' : select Text Click on Finish.