In theory the “in place” upgrade should work however there is a concern that the upgrade has the potential to break dependencies such as .NET and visual C++. This is because during Windows upgrades the redistributables including their dependencies, are added and/or deprecated. If a Windows upgrade was not fully successful for some reason this could occur, however it may be easily repaired by simply redownloading dependencies. . For example, we have seen OS upgrades that went smoothly however some failed to install “ALL” of the dependencies. This was easily resolved by redownloading C++ and .NET - and it one case manually adding the dependencies. A software called dependency walker may be an option to help resolve this particular issue.
We recommend the following:
If the DLP server fails to start, after the OS upgrade then we would could try re-downloading redistributables and confirm what is missing with the dependency walker tool as explained above, otherwise we are likely looking at performing a disaster recover reinstall of DLP.