Please see Crash Reporting.
If your computer can't handle Garry's Mod, things will often be slow. Alternatively, you might have spawned a lot of props or constraints or installed too many addons. Try removing some and see if that speeds things up.
Your Graphics card is either overheating or failing. Let your PC cool down.
If your Graphics card isn't hot make sure that you didn't enable a filter which can be enabled in the top left of the context menu or spawnlist (Or a post process found in the spawnlist)
- Right click on the left of the Q menu. Create a new category
- Right click on the newly created category, from here you can edit(rename, change icon) or delete it. You can also create more categories within it.
- Once you name your category, click the save button at the top.
- From there, you find the props you would like to add into the category, select them by click-dragging over them, and then drag them into it. You need to drag them over the category name, and then to the right into the spawnicon area.
- To add headers into your list, right click on the category name(or click that little [...] icon on the bottom) and click edit, then click and drag the icon into your list. Double click it to rename it.
- Make sure to click again when you are satisfied.
- Don't forget to save
If you're seeing black and purple, you are missing the texture for a certain object or part of the map. This can be caused by faulty installations or downloads of addons or games the server has mounted that you haven't.
You will first need to follow the detailed set of instructions.
- Open up your steam library (where you view your games)
- Right click on the game that you want the textures on Gmod to be updated and click "Properties"
- Click on the "LOCAL FILES" tab, in there click on the button "VERIFY INTEGRITY OF GAME CACHE..."
- Wait for it to finish validating the steam files.
- Once Finished with the validation process, complete all other necessary things it asks for on the screen.
- Finally, close steam, restart your computer, and then play Gmod without any missing textures.
The big red error sign is the Source Engines way of telling you that you are missing a game model. This may be caused by a gamemode or addon of the server that you are missing or a server-mounted game that is not mounted for you. As of now, Garry's Mod ships with low-res replacement textures/models for essential games like CS:S so you won't be seeing an error model for those.
Your addon may have been copied from Garry's Mod 12 to 13. It is most likely now incompatible. Garry's Mod 13 introduced a massive number of changes, most of which render addons created for Garry's Mod 12 incompatible with 13. Please make sure your addon is up to date.
You should report these errors to the developer of the addon, along with any information you can provide to help recreate the errors. This will help the developer fix the errors. Do **not** ask Garry to fix the addon, as he didn't create it.
Sometimes <!-- all the time --> an update to Garry's Mod or the underlying TF2 engine on which it is based will break part of the game, causing the addon to break as well. Garry may provide a fix for this, but otherwise it is up to the developer to fix the addon.
Some addons are only available in English. Alternatively, if you can provide a better translation, visit http://translate.garrysmod.com/.