Wildlands won't start.

- https://support.ubi.com/en-GB/faqs/000025721

Sometimes your anti-virus programm is blocking Wildlands. Just disable it before starting the game. You can turn it back on again afterwards.

- https://support.ubi.com/en-GB/faqs/000025662/Run-applications-with-administrator-rights

Ubisoft Connect app - https://support.ubisoft.com/en-GB/Article/000060529
Steam app - https://support.steampowered.com/kb_article.php?ref=2037-QEUH-3335&l=english

To do this, go to the Start menu on your desktop.
Type in %TEMP% and press enter.
Go to Edit and Select All.
Go to File and Delete.

Please use only the official manufacturer's Website to download the drivers:
Operating system update - https://support.microsoft.com/en-gb/help/12373/windows-update-faq
Clean installation of your graphic drivers - https://support.ubi.com/en-GB/faqs/000025720/

- https://support.microsoft.com/en-us/help/929833/use-the-system-file-checker-tool-to-repair-missing-or-corrupted-system

If you haven't already, to do this:

Open your Control Panel, and make sure to uninstall anything which is related to Microsoft Visual C++ Redistributable.

Once this is done, please download and install the following files :

Microsoft Visual C++ 2005: https://www.microsoft.com/en-us/download/details.aspx?id=21254
Microsoft Visual C++ 2008: http://www.microsoft.com/en-us/download/details.aspx?id=29
Microsoft Visual C++ 2010: http://www.microsoft.com/en-gb/download/details.aspx?id=14632
Microsoft Visual C++ 2012: http://www.microsoft.com/en-us/download/details.aspx?id=30679
Microsoft Visual C++ 2013: https://www.microsoft.com/en-us/download/details.aspx?id=40784
Microsoft Visual C++ 2015: https://www.microsoft.com/en-us/download/details.aspx?id=48145
Microsoft Visual C++ 2017: https://support.microsoft.com/en-gb/help/2977003/the-latest-supported-visual-c-downloads

Once you have reinstalled all the dependencies, restart your computer and try again.

To download and install DirectX, just follow this link:
https://www.microsoft.com/en-us/download/details.aspx?id=8109

To do this, go to the Control Panel.
Go to Programs, Uninstall a program.
Select Ubisoft Connect.

To re-install Ubisoft Connect, go to your game's local files.
Go to support and install UplayInstaller.exe

First thing you should try is deleting the Ubisoft Connect cache, it is known to cause issues with stating games after updates.

Close Ubisoft Connect (via task manager if it doesn't respond),
Go to C:\Program Files (x86)\Ubisoft\Ubisoft Game Launcher\cache,
Delete all content (even if a warning shows up),
Start game via Steam.

Credit goes to Alex Jones.

To re-install Easy Anti-Cheat, go to your game's local files.
Go to EasyAntiCheatand install EasyAntiCheat_Setup.exe

Credit goes to ♥TainakaOne♥.

Consider installing both Ubisoft Connect and Wildlands on the same same hard drive to avoid getting grw.exexe error.

Credit goes to Laurifer Panda.

Disable E-Cores and Hyperthreading within the system BIOS. While optional, overclocking the remaining P-Cores might help maintain performance. AMD-based systems typically do not encounter these issues as they do not utilize E-Cores or Hyperthreading.

If you still experience issues after following these steps, you can simply contact Ubisoft on https://support.ubi.com/en-US
They will take a closer look at the way this troubleshooting impacted on your system.

Special thanks to Ubisoft Customer Support and at Microsoft.

Further thanks to community feedback:

• Alex Jones
  
• ♥TainakaOne♥
  
• Laurifer Panda
  
• DAV3NATOR