When editing a maintenance plan (that I am newly creating) I got:
Exception from HRESULT: 0xC0010014 (Microsoft.SqlServer.DTSRuntimeWrap)
The issue is the client tools installed in %ProgramFiles(x86)% instead of %ProgramFiles% but instead of reinstalling client tools, I ran:
%windir%\syswow64\regsvr32 "%ProgramFiles(x86)%\Microsoft SQL Server\90 \dts\binn\dts.dll"
Which resolved the issue.
Hope this helps someone!