The most common reason for inability to open an email attachment is that the computer lacks the software for that sort of file. Attachments come from a variety of programs, and if the computer does not have the right program installed, the attachment will not open. Windows users will often see a pop-up screen asking if they want Windows to find the right software with its web service; however, if they keep their file extensions enabled and have a guide to extensions handy, they know which software they need.
One common problem with opening email attachments involves Microsoft Office. If a Word file is received but the user lacks the software, .doc and .docx files do not open. To avoid paying for the software, users can take advantage of Microsoft Office-type free programs like OpenOffice to view files. OpenOffice will open the .doc and .docx extensions, as well as other Office extensions like .ppt or .pptx (PowerPoint) and .xls or .xlsx (Excel).
If the user has an older Office version, he likely lacks the ability to open files with the .docx and .xlsx formats because older packages are incompatible with XML formats. However, converters are available online. Another common problem involves receiving multimedia files that do not play or open. QuickTime or RealPlayer files do not work with Windows Media Player so the correct player needs to be installed.