The demand for portable diagramming tools is valid and growing. Remote work, shared workstations, and locked-down corporate laptops make traditional installations painful. However, Microsoft Visio was never architected for this use case. The internet's offer of a "free portable Visio" is a honeypot designed to infect the impatient.
Download the offline version of draw.io (diagrams.net). Save the HTML file to your flash drive – open it in any browser on any Windows PC, no installation required. Supports .vsdx import/export, so you can work with Visio files too. portable download microsoft visio portable
Instead of risking unverified downloads, consider these legitimate ways to use Visio flexibly: The demand for portable diagramming tools is valid