There are a number of things that can cause the ConQuest has encountered a problem and needs to close message on startup.
If this is a new install, it's possible that the snapshot settings file has not been properly edited as per the instructions. Make sure that the chevrons from <changeme> were removed. The Snapshotsettings.xml file is located in the user's configuration folder. On Network installs a default folder is copied and renamed and the Window Username needs to be populated to replace the <changeme> section. Also, make sure that the ConQuest network drive is active and try again.If you have On-Screen Take-Off, it could be related to a problem with the RabbitMQ integration. If possible, get this service restarted.
It may also be a corruption in your layouts, especially if you've recently had a crash. The easiest way to resolve this is usually to take a copy of a colleague's layouts folder.
If running a Network installation it is possible the SQL server is struggling, ask IT to restart the ConQuest SQL Instance or the Server itself.
If an update has been run and you can no longer log in please continue with a support member.
If that does not help or you do not have a network install, if you can access your log file (usually C:\ConQuest Q Series\ log.txt) please attach it.