What Is an XLAM File?
A file with the XLAM file extension is an Excel Macro-Enabled Add-In file that’s used to add new functions to Excel. Like Excel’s XLSM and XLSX file formats, these add-in files are XML-based and saved with ZIP compression to reduce the overall size.
How to Open an XLAM File
XLAM files can be opened with Microsoft Excel 2007 and newer. Earlier versions of Excel can open one, too, but only if the Microsoft Office Compatibility Pack is installed. There are two primary methods for opening the file:
Open the XLAM File Through Excel’s Menu
Copy the XLAM Files to the AddIns Folder
Another option for opening the file that’s especially useful if you have more than one, is to put it in this folder so Excel will automatically load it when it opens: The other path is Developer > Add-Ins. See Microsoft how-to to learn how to enable the Developer tab if you don’t already see it. If your add-in is already listed in this window, just put a check next to the name to enable it.
How to Convert an XLAM File
There shouldn’t be any reason to use a file converter to save the file to a different format. While those tools do work for lots of file formats, this isn’t one of them. See this Excel Forum thread on converting XLAM to XLSM if you want to do that. It involves editing the IsAddIn property to False.
Still Can’t Open It?
If your file doesn’t open at this point, it’s highly likely you’re not dealing with an actual XLAM file. This might be the case if you’ve misread the file extension, which usually happens when the letters look a lot alike. For example, XAML could easily be confused for XLAM even though those files are used with a different program. AML and LXA are some others, where the format is either ACPI Machine Language or Arc Macro Language (for the former), or Microsoft Speech Lexicon (the latter). If you’re having trouble figuring out what to do, research the actual file extension at the end of your file to learn more about the format it might be in and find download links to the software you need to open/edit/convert it.