>>>>>I might be wrong, but I thought there was a tool that allows importing XLS files without having Excel installed?
>>>>
>>>>Unzip the xlsx, and then in the xl subfolder there's sheet1.xml, sheet2.xml etc. Then read the xml and get the values.
>>>
>>>PMFJI, but how do you Unzip an xlsx file? I am using legacy pkzip25.exe but I can't figure what you mean.
>>
>>Dmitry, if you rename the file's extension to zip, you can unzip directly from the Windows Explorer.
>
>You are right. Thank you, Antonio!

If I'm not mistaken ZIP file capability has been built-in as far back as WinMe and WinXP (where they were referred to as "compressed folders"). As previously mentioned, if you change the extension you can usually extract and add files through Explorer with the what is built into Windows without adding any software. There are occasions however that you may need the add-in software like PkZip for Windows, WinZip, WinRAR, etc. when you're dealing with ZIP archives that use some of the newer compression or encryption modes.