Shimadzu offers a (limited functionality, no instrument control) for free on their official website. While version 2.43 is not publicly linked, their current "UVProbe 2.43" (confusingly, they reuse version numbers) is sometimes available as a time-limited trial for academic teaching labs.
If you purchased a new Shimadzu spectrophotometer, the software CD should be in the documentation package. Contact Local Shimadzu Representative: uv probe 2.43 free download
If the goal is data analysis rather than instrument control, various open-source platforms (like R or Python libraries) can process spectrophotometry data without the legal or security baggage of pirated software. Conclusion Shimadzu offers a (limited functionality