Normally reinstalling Wot Numbers do not help on solving startup issues, but of course it do not harm trying repair or reinstall (uninstall/install). It can solve some issues. However, trying to reinstall multiple times will just be a waste of time...
The application stores all application settings in the application settings folder (appsetting folder):
The file: "config.json" in the appsetting folder stores all startup parameters, editing this file can solve startup problems if you can find incorrect settings in it. Deleting the file prepares Wot Number for a clean startup, as it was a first time install. A new config file will automatically be created if it does not exist. For more info check the user guide: 10 - Application Settings.
If you have problem after first time install, it could be that the initial database creation has failed. Deleting the config file and restarting Wot Numbers is then the best option. The system will suggest creating a new database. Important: leave your computer "alone" while it creates the database, it is a disk-intensive operation.
If Wot Numbers seems to start, but is not visible check this forum topic: What to do when Wot Numbers fails on startup without error message?
If deleting "config.json" does not help, checking the log file is the next step. Follow this Q&A forum topic to get some clues on how to do it: How to find log-file and understand content.
If log file is not present, or if the log file do not show any problems, it can be that the application terminates before logging starts. Go to Widows Event Viewer and check the application logs and look for errors. Wot Numbers requires Windows .NET 4.0 framework to be installed, check the System requirements for more information.
If an error message appear, please expand the error dialog window to see the whole content. Wot Numbers do run several tasks in the background, and some errors can happen without any error message . All errors, shown in a error message box or not, will be logged to the log file.
Follow this Q&A forum topic to get some clues on how to check and undersatand the log file: How to find log-file and understand content.
Search the forum for help using keywords from the error logging. If you cannot find any help solving your problem add some relevant error logging to describe your problem.
Wot Numbers fetch tank details using Wargaming API, and uses also API to WN8/9 to rating sites for getting correct parameters for calculating the ratings.
API = Application Programming Interface, normally it is a webservice provided at a site for others to fetch or commit data.
New tanks might be missing from these API's, and when this happens Wot Numbers will either assing some default data or the data will be missing.
You can look for updated tank data running the setting menu: "Download and Update Tanks". If tank data still is missing, you can manually add tank information by right click on a tank from the Tank view and select: "Edit Tank Info".
If new tank data are fetched or edited manually, run from settings menu: "Recalculate Tank Data" and "Recalculate Battle Ratings" to update your tank/battle data.