by Ken Task.
Click the link that is provided 'more information about this error'.
From the information provided, looks like you are remotely hosted. Use whatever tool you have to browse files/folders.
Look in: moodledata/filedir/60/98/ (those are folders)
for a file named:
609878ccc53cd3a33654be6958fee92eb6fac5a4
Is it there?
Also, with whatever tool you have to work with the database, run this query:
select * from `mdl_files` where `contenthash` like "%6098%";
To see information on that file. If it exist.
'spirit of sharing', Ken