When going through to repair your SU installation following SU support’s instructions, it would be a good idea to also following the tip from @MikeWayzovski to FIRST remove Microsoft Visual Studio C++ 2015 Redistributable from the Add/Remove Programs (SU17 requires VC++ 2015, not VC++ 2014 as mentioned above).
When you reinstalled SU17, its installer examines the computer environment. When the installer detects that VC++ 2015 is missing, it will ping MS and download and install a new version of VC++ 2015.
Dating back to last December, MS released a buggy version of VC++ 2015 and since then, at least one Win10 automatic update did something bad to make VC++2015 buggy. Also, on occasion, the SU installer could not install VC++ 2015. In that case, VC++ 2015 needed to be installed separately by the SU user. See the first post at Important Update on a few Potential SketchUp 2017 issues on Windows.