Currently having same issue. Full install of game and mods was a viable method however this issue is now persisting through multiple fresh installs.

Launcher Version: 1.5.150968

Game Version: 2.14.150957

Branch: Main

Having the same issue here. Attempts to import a preset by dragging and dropping the html file into the launcher, selecting 'import' from the preset drop-down in the top-right, and selecting 'import list of mods from a file' from the '...more' option all provide the same "Unable to import preset" error message.

Worth noting the drag-and-drop method will download any mods that I do not currently have, but still does not build the preset.

I have fully deleted and reinstalled Arma 3, including clearing my AppData, and the issue persists.

Launcher version: 1.5.150968

Game version: 2.14.150957

Branch: Main

I had the same problem when trying to import a preset from an html file I was sent. I have found the error - the output html file is formatted incorrectly - I edited the html and file now imports!

I tested by exporting a small list of mods and then reimported to a preset. That worked.

So then I compared the working html file and discovered the formatting error in the html file I was sent. So I fixed the html file and its fine. So someone who created that html file I was sent must have used a different prog to format it and save it. It has a table format that is incorrect. So the launcher export output to html works fine and so does the import of html to Preset.

The log error seems to refer: PresetsViewModel: System.Xml.XmlException: The 'link' start tag on line 8 position 6 does not match the end tag of 'head'. Line 80, position 5.

So the file could not be parsed correctly.

Seems like there's multiple causes then, because the only way I got my launcher to successfully load presets and mods was by doing a factory reset and selecting the keep my files option. It worked, and I haven't had the issue since. My issue likely wasn't that the HTMLs were formatted wrong since everyone I knew could load the same HTMLs perfectly fine.

The last resort I can suggest is just factory resetting your PC - backup everything you want and factory reset. It should fix it, it did in my case.

You are correct there is more than one issue here. FYI I also cleared the Appdata A3 Launcher folder. (first backed up the presets and other settings.) to force reacquisition/repair of these Launcher files. I also cleared the Steam Apps Common Redistributables folder to force reacquire (C:\Program Files (x86)\Steam\steamapps\common\Steamworks Shared\_CommonRedist). This seemed to also resolve a C++ lib problem in C:\Program Files (x86)\Steam\steamapps\common\Steamworks Shared\_CommonRedist\vcredist. Once I had cleared these files - I got Steam to revalidate the local file cache of Steamworks Common Redistributables - Steam then reacquired the above files.