Thank you for your question.
We could help you better if you could clarify some details for us. Can you tell if you are working on teamwork server projects, or on locally saved projects? Do you have a previous version of project, which is common for the projects on both networks?
MagicDraw does not offer projects merge during copy/paste project files. However MagicDraw offers possibility to merge models through application. To Merge locally saved projects please use command Tools > Project Merge. Basically, if you are sure that there are no conflicting changes (e.g. in same element property or same module), you can use 2-way merge - then changes from both projects will be accepted and merged into one project. If you have conflicting changes and have a common ancestor project both projects split from, it is advised to use 3-way merge and resolve conflicts manually.
To read more details about Model Merge, please look in MagicDraw User Manual (you can find it in your MagicDraw <install.root>/manuals or open using Help > MagicDraw User Manual command), under section Model Merge.
If you have more questions about merging your projects, please do not hesitate to contact us with additional details.
Looking forward to hearing from you,
No Magic Customer Support