Search for and place the following components in your schematic (ISIS):

This is a common pitfall. Proteus excels at simulating digital logic, microcontrollers, and even analog circuits. However, specialized interface components like the MCP2551 are often absent from the default library because their behavior involves complex analog characteristics: slew rate limiting, differential voltage thresholds, common-mode rejection, and thermal shutdown.

Here are the best places to search:

The MCP2551 handles the differential transmit and receive capabilities for the CAN protocol controller. It operates at speeds up to 1 Mb/s and provides shift signaling compatibility, temporary protection against short circuits, and RF interference immunity. Simulating the MCP2551 in Proteus allows you to:

Restart Proteus, right-click the MCP2551 component, select , and link the downloaded program/model file to the component. Best Practices for CAN Bus Virtual Prototyping

Are you getting a specific when running the simulation?

: Run your initial simulations using a single transmitter and the Proteus CAN Analyzer. Once the analyzer successfully registers the packets, add your receiving nodes and MCP2551 hardware layers.

Which (e.g., Arduino, PIC, STM32) are you pairing with the MCP2551?