What Is a FOB File?

How to Open, Edit, & Convert FOB Files

Screenshot of several FOB files in Windows 10
FOB Files.

A file with the FOB file extension is a Dynamics NAV Object Container file created with Microsoft's business management software Microsoft Dynamics NAV. These are files that reference objects like tables and forms that Dynamics NAV can use.

The .FBK file extension is used to indicate an object backup file, which of course is also used in the Microsoft Dynamics NAV program.

FOB files might also be referred to as Navision Attain Object files or Financials Object files.

Note: FOB files are not in any way related to a key fob, which is a small device used to access remote devices, much like a digital key.

How to Open a FOB File

FOB files can be opened with Microsoft Dynamics NAV (it was previously called Microsoft Navision). In the development environment, first access the Tools > Object Designer option from the menu (or hit Shift+F12), and then File > Import... in the new window to select the FOB file.

Finn's FobView is a small portable program (it can run without being installed) that can be used to open FOB files as well as to compare two files for differences. It also supports FBK, TXT, and XML files that were created in Microsoft Dynamics NAV.

I'm not entirely sure if this will work, but you may also be able to open FOB files with a text editor so that you can read the text version of the file. Please know, however, that doing this won't make the file functional like if you were to open it with Microsoft's program. All you could really do is edit the contents of the file, like maybe any references that it has. See our Best Free Text Editors list for our favorites.

Some FOB files may instead be a type of image file exported with IBM FileNet Content Manager. I'm not sure of the specifics but I know that some users of that software have had the program export an image with the wrong extension, as .FOB, even though it should be BMP, TIFF, or some other format. If this is how you got your FOB file, then renaming it with the proper file extension may be all you need to do to open it with your favorite image viewer.

Note: Renaming a file like this is not the same as converting it. All this is doing in this context is putting the correct file extension at the end of the file because the IBM program didn't do it.

If you find that an application on your PC does try to open the FOB file but it's the wrong application or if you would rather have another installed program open FOB files, see our How to Change the Default Program for a Specific File Extension guide for making that change in Windows.

How to Convert a FOB File

Microsoft Dynamics NAV should be able to export an open FOB file to a TXT file. This is likely accomplished through its File > Export menu.

The Finn's FobView program mentioned above can export a FOB file to CSV.

Still Can't Open Your File?

If you can't open your FOB file with the programs mentioned above, be sure you aren't confusing it with another, similarly named extension. Some files use a similar file extension but it doesn't necessarily mean that the formats are the same or that they can be opened with the same software.

For example, consider that your file might be a VOB or FOW (Family Origins) file, which do not open with the same program that FOB files open with.

If you double check the file extension to find that you don't really have a FOB file, research the actual file extension to learn which software programs can be used to open or convert the file.

However, if you do have a FOB file and it's not working like we describe on this page, see Get More Help for information about contacting me on social networks or via email, posting on tech support forums, and more. Let me know what kinds of problems you're having with opening or using the FOB file, what exactly you're trying to do with it, and then I'll see what I can do to help.