The document "x" could not be saved (EXTERNAL DISK)

I have big sur 11.6.2 operating system, and I have partitioned my hard drive, my main partition has rhinoceros installed, and in the secondary partition I have the rhino files saved, my problem is when I open a file from my secondary drive I can work the file , but when I want to save it, it won’t let me. I get the legend “Your changes will not be saved until the problem is resolved. You can also duplicate the document or discard your changes to close it.” and I can not save changes I must duplicate the file and then replace with the new modified. None of this happens when I open and modify the file from my main partition, it only happens if I open and modify the file from my secondary partition where rhino is not installed.