Ainda não é possível, como já foi respondido aqui . Você pode usar somente uma abordagem alternativa descrita aqui :
Stop double-clicking the .TXT/.CSV file or opening the text file conventionally (e.g. CTRL+O) and use the Text Import Wizard to specify Text format for certain fields within your import file. Start by opening Excel to a blank workbook and from the Data tab's Get External Data group, click the From Text button.
After clicking From Text, select your text file from the Import Text File dialog and click Open. This launches the Text Import Wizard. There are three pages to complete. The first page is essentially to determine whether the file is to be considered Delimited or Fixed Width. The second page depends upon the first. You will be asked what characters to consider as delimiters or asked to choose the widths of a fixed width file.
The third page is what is going to help you determine the format of each field. Select your account id field from the Data preview at the bottom then select Text from the Column data format list in the upper left. Note that the header of the field in the bottom Data preview has changed to Text. Repeat for any other fields and click Finish in the lower right to complete your operation.
Outra maneira é usar o script VBA, como aquele aqui .