To reproduce:

1. Download and open attached "repro925490.zip" project.
2. Go to build settings and make sure that Build System is set to Gradle and "Export Project" option is enabled.
3. Export the project.

Expected result: Project is exported successfully. No errors are thrown.
Actual result: Unity fails to export the project. "IOException: Win32 IO returned 267" error appears.

Reproduced with: 2017.2.0b2, 2017.1.0f2, 5.6.2p1, 5.5.4p1, 5.4.5p3.

Notes: 5.4 does not have Gradle, but it still possible to export as GoogleAndroid project. It returns same error as in never versions. Exporting with ADT(legacy) selected returns same error. In this case user had ":" character in Product Name.

Verified with: 2017.3.0b1