@onlyAgamer,
thank you for the logs. I've review them and the crash occurs while loading user interface deeply in Microsoft code, and I believe that it's because some files might be corrupted.

Could you please open this folder C:\Program Files (x86)\Steam\steamapps\common\Arma 3\Launcher
and delete pt-PB folder there, and then go one level up to Arma 3 folder and delete the folder also from there (if it exists, but it should not be there) and try Launcher again?
It that doesn't help, delete entire Launcher folder and let Steam to re-download the data: https://support.steampowered.com/kb_article.php?ref=2037-QEUH-3335

@BISWizard I had a look and the closest folder I found to the name was Pt-Br I take it this is the one you meant, I deleted it and tried again, same issue, so I deleted the whole Launcher folder. and re-verified my files, let them download and tried again, still crashes instantly

@onlyAgamer: could you please download and try these two versions of Launcher?

• http://arma.jiripolasek.com/files/Launcher_139586.zip
• http://arma.jiripolasek.com/files/Launcher_140900.zip

Also when was the last time you was able to run Launcher successfully?

Edit: could you please look into folder C:\Users\onlyAgamer\AppData\Local\Arma 3 Launcher for recent files with the .mdmp extension?

@BISWizard Sorry for late reply, just got some free time to test both of these, simply drag and dropping and replacing any files, sadly though both of these had the same result for me and both instantly crashed when I clicked play on steam. and as for when i was last able to use the Launcher, I last used it the night before 1.68

Had a look for any files with .mdmp this is my most recent one, seems so be from 6 days ago.

Edit (file uploaded)

@onlyAgamer: could you please try to run version 139586 without moving it Arma installation folder (just unpack it to a separate folder) ? That version is what the one we've distributed with 1.66 so should run.