NET6 ​​regarding package downgrade error reporting

NET6 ​​regarding package downgrade error reporting After my colleague updated the package two days ago, he found that the relevant authorization was not in place (I did not buy this version), so I needed to downgrade it back to the original version. Originally, when I didn’t pull the latest version locally, there was no problem compiling it, but when I modified it after the update, there was a problem. Severity Code Description Project File Line Suppression StateError NU1605 Warning As Error: Detected package downgrade: ExcelUtilCore from 1.1.0 to 1.0.2. Reference the package directly from the project to select a different version. After searching online for a long time, most of them are package problems with .NET platform upgrade. There is very little information about 1605 and it is not accurate, so I will record it. 1. Why is the error reported In the project property, the default 1605 is used as an error 2. Processing method 　It is useless to remove 1605 and recompile in the settings. At this time, the following code will be generated 　$(WarningsAsErrors) 　$(WarningsAsErrors) 　$(WarningsAsErrors) is not what we need. We need to add NU1605 to compile successfully. So the correct configuration is as follows 　NU1605…