Despooler failed to execute the instruction, error code = 8 love

When you get this error, it means your disk is not enough.

Scenario: DC+CAS+PE1,PE2

Problem:

Distribution a WIM file failed and I get error as following:

Message ID: 4402

Despooler failed to merge delta to the compressed package "CAR0000E". The operating system reported error 1295: The requested file operation failed because the storage quota was exceeded. To free up disk space, move files to a different location or delete unnecessary files. For more information, contact your system administrator. 

Possible cause: The destination drive is full.
Solution: Make more space available on that drive. Despooler will attempt to merge the delta again during its next retry interval

 Go to Monitoring-- > Distribution Status -- > Content Status selected my pkg -- > View Status. In Error tab, I get a message said "Disk is not enough". But when I check my Primary Site, 5G disk is free status.

Why????

 Let's open despool.og:

 

Ah~~ I think I get it.

Free more disk on my PE site, make sure it has 10G disk available

OR

Your current available Disk = Failed pkg size * 2

 

 and re-update this pkg, problem resolved.

Why??

1. PE will get pkg from CAS and stored at file://pesite/C$/SMSPKG/pkgnumber.PCK

2. Then an other file will be created at same path, same size (maybe bigger) but different with the pkg name.

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But here is another question, when I check dspool.log, following message make me very confused.

 Error code is 8, the code description from http://support.microsoft.com/kb/122177 you can see,,,

8      The share name for a sharing job cannot be ADMIN$ share or any
       rootdrive$ share. Hidden shares are supported, they just can't be
       any existing system hidden shares. Please use a share name other
       than X and resend the package.

In fact, this problem has nothing to do with permissions,,,,, why?? why?? only Microsoft knows