You cannot backup Exchange via a shares or the file system, even with Snapshot technology enabled, the Exchange files are ignored because Active File Exclusion (AFE) blocks the backup.
Hence if you run a job with only Exchange files selected you will get a resources specified have no valid data message as trhere is nothing to backup that is not blocked by AFE
You should be backing up the Exchange Information Stores with our Exchange Agent (which also makes use of VSS but also uses the Exchnage API from Microsoft to protect the system). Note The Exchange agent needs licensing.
If you use the Exchnage agent you also get individual e-mail restore and Exchange log truncation, both of which would also not be possible with a file system backup of the Exchange files.
If using the Exch agent, uncheck the AOFO option from the backup job properties...
Regarding checkpoint restart, have a look at this KB article - http://www.symantec.com/business/support/index?page=content&id=HOWTO74232
If I am right, you are backing up the Information store using Exchange agent to a backup to disk on a network share. check the following steps:
1) Whether or not Advanced open file option used, its by default a Snapshot based backup. so you can leave that option enabled. And you can disable Check point restart, Refer article http://www.symantec.com/docs/HOWTO74232
2) In the failed job log, make sure to check, to which database the error occurred. Sometimes issue might be on specific database after backing some other databases or it can fail immediately without any byte count.
3) Make sure to check the timestamp of error in job log and compare it with the Application even viewer on Exchange server ( source could be from ESE or MSExchangeIS or VSS)
4) Check the status of writers on Exchange server to find out which writer had failed which requires reboot by running cmd "vssadmin list writers".
5) Make sure that the backup time window does not conflict Exchange database maintenance time window.