If any bug is reproducible only on Testing server and not on Development server, how you make sure that the developer fixes that bug?

The steps or scenario carried out to reproduce defect at test environment but the same steps carried out at development server if does not produce defect. It may happen that there can be some files missing at test environment, code changes at development server due to update on build. Tester has to reproduce the defect carefully conducting steps at development server and advice developer to fix the defect.