Nitro PDF 12 Hangs on startup - minimized window

[AD2018]

I have been using Nitro 12 in Windows 10 for a while with no issues.  Today it just stopped working - it "starts" but stays minimized on the task bar and when hover over it it shows a Nitro window, but clicking on it does not open or maximize the window .   I tried repairing installation and completely uninstalling and reinstalling, running as administrator,  and nothing has solved the problem.  On the last re-install I was hopeful because I at least got to the registration screen, but after entering my serial number, it still doesn't work.

One bit of (maybe) relevant information -  I read on some other posts that there is a problem with the Brother ControlCenter (printer) conflicting with Nitro installations.  I have a Brother printer and normally run the ControlCenter in the system tray.  So I disabled all the Brother background apps before the last installation and got no install conflict messages.  Install completed but Nitro still doesn't run...

Need some help figuring this out...

 

[Allain Umailin]

Hello @AD2018,

Thank you for reaching out to us through our Community Forums!

Do you have multiple monitors? When Nitro Pro is opened on a monitor that is later disconnected, it won't default to a current "active" display which causes Nitro Pro to display on the missing monitor. Kindly try these steps:

1. Try rebooting your machine.
2. If not fixed after rebooting, focus on Nitro Pro by clicking on it on the Taskbar. 
3. Press the Windows key + Left/Right arrow until Nitro Pro appears.

If above doesn't help, please provide me with the following:
-Any changes you're aware of before this happened like installing any major Windows Updates?
-What OS is installed in your computer (Windows 7, 8.0, 8.1 or 10 and whether it is 32-bit or 64 bit)?
-What build of Nitro Pro are you working with? You can go to Control Panel > Programs and Features (format is 10.X.X.X)

Thank you and I look forward to hearing back from you.