The file extension XLW5 was used by version 5 of the Microsoft Excel spreadsheet for the Apple Macintosh for workbooks. Several versions of Excel for the Apple MacIntosh used templates ending in xlw followed by the version number of Excel.
The default version of this type of file is xls or since the 2007 version of the Microsoft Office xlsx.
Most often resolving problems with opening XLW5 files is very simple. Just install an appropriate program that supports such files. All of the listed programs support XLW5 files, but may vary in offered function and purpose. Some programs may be capable only of viewing contents of XLW5 files or offer file conversion options, but may not be capable of editing such files.
It is possible that although a compatible program has been installed on user’s system, it is not used by the system to open it. This may happen because no default application was associated with this type of files. To associate XLW5 files with given application, select "Open with" from drop-down menu (accessed by right-clicking on the file). Then select from the list the program or application you want to be used to open this type of file. If the Microsoft Excel applications is not on the list, select "Browse" option in order to manually locate the directory where Microsoft Excel has been installed.
Sometimes problems with opening XLW5 files may not lie with the application itself, but can arise due to other causes, such as: