pictures download out of sequence

hi everyone. some help needed. when i download pics from camera to computer, if using my 6d or 7d, they download out of numerical sequence. when using a 1d mk3 or mk4 they download correctly.has it something to do with 8c8d and img? file numbers preceeded with img are the out of sequence where file numbers preceeded with 8c8d are in sequence. if i have hit upon the problem, how do i change img to 8c8d? or am i way off the reason? i am talking of canon cameras.

Not sure what exactly you are asking but the order files are downloaded is irrelevant. The order the files are displayed are governed by your sorting criteria.

What is 8c8d?

Windows or Mac? Can you tell if the files are sorted in Explorer or Finder by a different manner? Maybe by file size?

Both. Windows and mac.

Using Bridge or Lightroom (or any other tool) sort by date modified, rename to whatever naming convention you want. I use

EventName001.cr2