The r9 mart server is not designed to let multiple users save changes to the same model simultaneously. The user needs to wait until the first modeler's save changes is complete. Then they will be able to save their changes to the same model.
The solution is to use best practices and communicate effectively amongst the modelers to avoid a collision. Here are some suggestions:
- Use instant messenger and IM the other modelers. ‘Hey, I’m saving this model’. Or another message. Or use email.
- And /or set one of the locks on the model prior to saving changes. Then the other modelers can first check if someone else already locked the model before saving their changes.
NOTE: in r9.8 and later versions the mart server now includes an Incremental Save progress bar. Also, if another user tries to save into the same model, a message is displayed, which informs about the progress of the other user's save operation.