c# - Using different version of DLL -

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• loading assemblies , versioning 3 answers
• use different versions of dll file in 1 app 2 answers

i have problem third party libraries.

the main project using 1 of third party library has dependency; old version of newtonsoft.

i've created new project using third party library required newtonsoft newer version. tested functions , works fine.

but once call in main project, got errors

"additional information: not load file or assembly 'newtonsoft.json, version=7.0.0.0"

i cannot update older version in main project & might have conflicts.

how can use 2 different versions of same dll in main project?