Error code 0x40 when you try to open Office 365 ProPlus applications.

Problem: 


Error code 0x40 when you try to open Office 365 ProPlus applications

Solution:

To resolve this issue, follow these steps:
Enable application logging. To do this, follow these steps:
Enable verbose logging before you collect the log files.
Click Start, and then click All Programs.
Click Accessories, and then click Run.
Type reg add HKEY_CURRENT_USER\Software\Microsoft\Office\15.0\Common\Debug /v TCOTrace /t REG_DWORD /d 1.
Click OK.
Open the application to reproduce the error.
Review the error log that is located in the Temp folder. To find the Temp folder, follow these steps:
Click Start, and then click All Programs.
Click Accessories, and then click Run.
Type %temp%, and then click OK.

The following log files may be present in the Temp folder:
Bootstrapper*.log
c2r_*.log
C2RIntegrator*.log
Firefly*.log
Integratedoffice.exe_c2r*.log
Interceptor*.log
*.exe.log
*_c2rdll*

Note "c2r" is for Click-to-Run.

The log file to look for is named for the application that you use to reproduce the error. For example, if you use Microsoft Word to reproduce the error, you should look for the "winword.exe.log" file. You can select the appropriate log file from the following file names:
winword.exe.log
excel.exe.log
lync.exe.log
onenote.exe.log
powerpnt.exe.log
visio.exe.log
access.exe.log
publisher.exe.log
outlook.exe.log
project.exe.log
winproj.exe.log

Verify server connectivity.

Office 365 ProPlus requires Internet connectivity to the Office Subscription Service (OSS) to keep Office open and fully functional. To verify that you can connect, open a browser, and then try to access the following website:
MonitoredAPIService Service
If you still receive an "Internet connection required" error message when you start Office 365 ProPlus though you can open the link, follow the steps at the following Microsoft TechNet website:
General troubleshooting in Office 365 ProPlus
Disable application logging. To do this, follow these steps:
Enable verbose logging before you collect the log files.
Click Start, and then click All Programs.
Click Accessories, and then click Run.
Type reg add HKEY_CURRENT_USER\Software\Microsoft\Office\15.0\Common\Debug /v TCOTrace /t REG_DWORD /d 0.
Click OK.