I use OS X Mavericks 10.9.4.
I changed my username and this may have caused that I am not able to open any files. I still can see my PDFs and photos in Preview! I get this:
File XYZ couldn’t be opened because you don’t have permission to view it.
I have tried to run Repair Permissions in Disk Utility but that didn't help. I tried manually
chmod files but didn't have a permission to do that.
The strangest thing is that I can see my photos in Preview but when I open them I get the error.
The files are not locked. The folder is not locked too and in permissions tab I can see my username "Lukas (Me)" as "Read Write" access.