j-watt,
I completely agree. It is weird that the problem came out of nowhere. I didn't even update Maya, unless the issue came from a recent Windows 10 update.
The way that I fixed it was by uninstalling Maya 2018, then going into the files below to make sure that there were no Maya 2018 files in them.
- C:\Program Files\Autodesk\
- C:\ProgramData\Autodesk\
- C:\Program Files (x86)\Autodesk\
- C:\Users\All Users\Autodesk\
- C:\Users\**YOUR USERID**\AppData\Roaming\Autodesk\
- C:\Users\**YOUR USERID**\AppData\Local\Autodesk\
I then,
- Open My Computer
- Right-click the system drive, and then select Properties
- On the General tab, click Disk Cleanup
- Scroll down in the Files To Delete list, and then select Temporary Files.
- Click OK, and then click Yes to confirm deletion.
- Close the system drive Properties dialog box.
cite: https://helpx.adobe.com/x-productkb/global/delete-temporary-files-using-disk-1.html
I installed Maya 2018 normally. Once the install is done the installer will ask you if you want to Launch Now the program. I did that to make sure it opened. It worked for me. I also made sure the program opened several times to make sure.
I hope this helps you. I believe I also restarted my computer after uninstalling Maya 2018, I don't see that contributing to it working for me, but I figured I would mention it. Sorry for the wordy response.
Best,
Tom