**URGENT** PROS cannot upload, invalid start byte

I upgraded a project to the latest PROS kernel and when attempting to upload it gave me this error! image

I tried restarting pros, restarting the computer, fresh projects, other projects, downgrading, clean building, etc… nothing will let me download any projects at all. Corrupted files?

Urgent, comp tomorrow and not all the autons are saved on to the robot yet!!! PLEASE HELP!

Before you try anything, make a copy of your entire directory structure holding your code.


I’m not sure if this is the same problem but it involved python so it may work.

See if running the make clean from the cli works.
list your main directory content and also your src content here. if you upgraded from 3.1.6 there is a new main.cpp file that may be causing an issue.

@Johnmandrake i’m way past my knowledge base so …

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I feel like the issue of people putting URGENT in the title needs to be addressed. Your issue probably isn’t more important than everyone else on here trying to get help. It adds nothing to the discussion and makes your post spam-y.

That being said, make clean and maybe even running the PROS installer to repair your installation are probably your best bet.


I’m not the most familiar with the cli, but I think you have a corrupted file somewhere looking at those stack traces. My guess is that it’s the local project.pros file. If you make a brand new project, does it upload fine? If so, you might try deleting all the local files and remaking the various pros project file (or just moving everything over to a separate project). If not, it’s possibly some global file we make (you might try renaming the file in the link rpm posted and see if it makes a difference then). You can also peruse through the files in something that shows bad utf8 (I think notepad++ does), as it should be extremely obvious that the first character is bad.


You might also try deleting all of your programs off of the v5 (prosv5 v5 rm-all) on the command line.