Distribution package failed on distribution Point.

Hi

I have some issue with my distribution points.

Some of them don't work don't receive my packages. the DP configuration is OK.

The SCCM Server Acount Is administrator on the DPs. The 4 folders Are created succefully.

Some it s working properly and somtine it give th'is message: 

Distribution Manager failed to access the source directory....

Possible cause: distribution Manager doesn't have sufficient rights 

Possible cause There is no enough disc space available....

When i see the pkgxferMgr.log ihave this error:

CSendFileAction::AddFile failed; 0x8007050f

Failed to add the file FramePkg.exe in content P01002FF.1. Error 0x8007050f

CSendFileAction::AddFileMetaData failed; 0x8007050f

CSendFileAction::SendFiles failed; 0x8007050f

CSendFileAction::SendContent failed; 0x8007050f

 Sending failed. Failure count = 2, Restart time = 15/12/2015 12:30:08 Romance Standard TimeSMS_PACKAGE_TRANSFER_MANAGER15/12/2015 12:00:087016 (0x1B68)

I have this issue on differents DPs. When i remove and add the distribution point rule. somtime the problem is resolved sometime no......

Any idea to resolve my problem.

Thanks in advance.