Software & Apps File Types What Is an XLM File? How to Open, Edit, & Convert XLM Files by Tim Fisher General Manager, VP, Lifewire.com Tim Fisher has 30+ years' professional technology support experience. He writes troubleshooting content and is the General Manager of Lifewire. our editorial process Facebook Twitter LinkedIn Tim Fisher Updated on June 24, 2020 File Types Design Cryptocurrency MS Office Windows Linux Google Drive Apps File Types Backup & Utilities View More Tweet Share Email A file with the XLM file extension is an Excel 4.0 Macro file. Macros allow automation so that repetitive tasks can be "played" to save time and lower the likelihood of errors. Newer Excel formats like XLSM and XLTM are similar in that they can store macros, but unlike XLM files, they're actual spreadsheets that include macros. An XLM file is an outdated format that is, in and of itself, a macro file. It may seem like the XLM and XML formats are similar since their file extensions look the same, but they're actually two entirely different file formats. How to Open an XLM File While Microsoft suggests that you no longer use them, you can still open XLM files with Microsoft Excel. Microsoft's free Excel Viewer lets you open them without Microsoft Excel, as does LibreOffice Calc. It's important to take great care when opening executable file formats like .XLM files that you may have received via email or downloaded from websites you're not familiar with. If you find that an application on your PC does try to open the file but it's the wrong application or you'd rather have another installed program open it, you can change the default program that opens XLM files. How to Convert an XLM File You may be able to open an XLM file in Microsoft Excel or LibreOffice Calc and then save the open file to another similar format. If you're trying to figure out how to convert an XML file, learn more about that file format to see how to do just that. Still Can't Open the File? If your file won't open at this point and you're sure you're not confusing it for an XML file, you might still be misreading the file extension. Some files use an extension that closely resembles XLM even if the formats aren't related. XMI is one example. That last letter is a lowercase "i" and the file extension could be used for extended MIDI files. If so, you need a program like Winamp to open it. A similar file extension is LMX. Although it contains all the same letters as this file, it's used for Landmark Exchange files and can be opened with Nokia PC Suite.