Fix: MSB3027 Could not copy X to Y. Exceeded retry count of 10. Failed
MSB3027 means MSBuild retried a file copy 10 times and a process still held the destination. Kill the locking process, exclude bin/obj from antivirus, or raise CopyRetryCount.
csproj
2 posts
Fix: The type or namespace name 'X' could not be found (after adding a project reference)
CS0246 right after a fresh ProjectReference is almost always a TargetFramework mismatch, a stale obj folder, or a missing using directive. Five fixes in order of likelihood.