Below are a few common solutions to fix servers that won't start.
Use a default map
Editing your map list to contain only default maps is one easy check to determine if your custom maps or map list is to blame for crashing or not allowing your server to start.
For example, for CS:GO try loading de_dust2, For Team Fortress 2 try cft_2fort.
Removing addons using ClanForge can potentially allow you to start the server as your addons can conflict, and cause the server to crash.
Create new Profile
Creating a new profile is a suggested step, as it essentially provides you with a blank canvas. If creating a new profile allows you to start your server the problem will be likely something which was edited or customized since you started using your original Profile.
CSGO Token / Lan Mode Only:
All admins must create a unique token for their servers, without this token your server will be unable to start and won’t show in the steam browser list. We have created an easy way to do this via Clanforge.
On this page it will request an App ID - Input value 730
It will also ask for a memo - My Multiplay Gameserver
2. Once you receive your token, go to Clanforge -> Edit Profile
Under the settings tab you will see a new line for Gameserver Token
6. Enter the token provided on the website into this field then save and apply your profile.
The above can only be done if the following conditions are met.
You must own a valid steam copy of CS:GO
You will need a valid telephone or mobile number
You must have a non banned steam account.