We are running SP2013 and having often problems after deploying and creating a new site.
When the solutions are deployed, we create a site with powershell or from central admin with de new deployed WebTemplate.
When we open the site we get one of the following errors:
403 FORBIDDEN
The website declined to show this webpage HTTP 403 Most likely causes: This website requires you to log in. What you can try: Go back to the previous page.
The HTTP request to 'xxxx/SecurityTokenServiceApplication/securitytoken.svc' has exceeded the allotted timeout of 00:00:00. The time allotted to this operation may have been a portion of a longer timeout
Often after we got the error and we refresh the page the site will load and work properly, but sometimes loading of the site takes forever and a reboot of the server is needed.