Data Decompression Failed

[Sasan]

Hello,
when we  do our renders using Boxx Apext T3 (uses Corona 6). when renders are finished and saved as CXR, upon opening the CXR file, we get this error ( Data Decompression Fialed) for like half of our renders. the render elements cxr work just fine, it's just the main render with this problem.
PS, We have 3 computers , 2 of them use Corona 6 and 1 uses Corona 5.2. this error has been showing ever since we upgraded to Corona 6.