Tks it solved the problem.
I'm using a task to compile all our site to a zip file and later upload it to ftp to another server. Our site has a lot of files being created and deleted in real-time and VisualCron almost always retrieves the error:
"The file cannot be open for reading. Type Xceed.filesystem.diskfile." and then file name. I presume this is caused because when the zip is created the file listed doesn't exist anymore. Is there any way to avoid this error which is not enabling us to backup the entire site? We cannot backup folder by folder as we would need to add/deleted folder each time the site is changed.