Add the guides to their own layer, change the layer color by double-clicking on it in the layers palette. If it still looks wrong, you need to check your display settings on your system, especially if you are not using the native resolution of your screen. Colors could simply be interpolated due to scaling the interface.
Sorry to hear about this experience. I hope the suggestions shared by Mylenium helped resolve the problem. If not, kindly try pressing Cmd + E for macOS / Ctrl +E for Windows and check if it helps.
Also, please share some more information, like the exact version of the OS/Illustrator installed on your computer and the system configuration (CPU/GPU/Memory/Display Monitor), so we can investigate this further.
Looking forward to your response.
Hello, thank you for your response. 👋
(Photo 1) I have this problem with the guide: the clarity is very low and it is not possible to perceive on the work table despite changing the color of the guide.
(photo 2) This is how it is supposed to look, and it was like this before.
:desktop_computer:️: iMac 2017, radeon pro 570 4gb, core i5 3,4 Ghz, 16 ram
Adobe illustrator 2013 v 27.1.1
(photo 2) This is how it is supposed to look, and it was like this before.By @ronhuanca
Before what happened?
Did you get a larger screen? Update the system? Update Illustrator?
If nothing else helps, try and change the color of guides to something darker.
Does it change when you turn off "Draw in Realtime"
Or is it different when you turn off the GPU Preview?