What can you do if you're installing an expansion card and it doesn't fit?

If an expansion card doesn't fit, first ensure that you are attempting to install it in the correct slot and that the slot is compatible with the card type. Check for any obstructions, such as cables or other components, that might be blocking the installation. If the card still won't fit, verify that you have the correct card for your motherboard and consider consulting the motherboard's manual for guidance. If necessary, you may need to adjust or remove components to create sufficient space for the card.