Now if you have started with MS office 2007 then this office will open the XML format files and these files have also became a default opener. MS office also provides the support to read ECMA-376, and even read and write support for ISO/IEC transitional. This format was at first consistent by ECMA.
In early 21th century like in 2000 MS released the first version of XML (extensible markup language) whose format was based for MS excel. This thing was combined in Office XP. A new and latest file format was invented for Microsoft Word File in year 2002.
In addition to the problem described above, i.e. the lack of the appropriate application to support the .XLSX file, there may be several reasons that cause problems with opening and operation of the data format:
A quite common problem is the lack of application in the appropriate version. Even if you have an application, with the help of which you should open the .XLSX file, you may have a problem with it because of its version. Perhaps in previous versions the application has not yet supported the .XLSX file, so download the update and check again.
If you have already installed the appropriate application, and it is the correct version, the file may not open correctly, because the operating system does not have information that this program supports the file. So you need to "show" which program the computer should use. To do this:
It also happens that the file you want to open is corrupt and therefore there is no such possibility. In this situation, you should find its different version, or ask a person from whom you got, to send it again.