Troubleshooting: SoftException in Application.cpp:544 | Josh Highland
This is a more detailed explanation on softexception it is the way your apache is setup.
In most servers to upload a file to a folder the directory needs to be 777 permissions. Now on a small amount of servers you can upload and create folders with 755 permissions. You can test this by setting your data and uploads folders recursively to 755 permissions. If you can create a category and upload and delete images from that category then your app will work with 755 permissions. That will most definately get rid of that server error. Now if you application will not work with 755 permissions then of course you will need to set permissions back to 777.