some .asax .svc files become empty after deploy

We use msdeploy V3  to push our services(about 10 services) to AWS EC2.

Here is step in script:

1.Create instance in AWS.

2.Deploy all services to the instance created in step 1 one by one.

3.Terminate the instance created in step 1.

4.Snap a new image based on the instance terminated in step 3.

5.Launch instances based on the new image snapped in step 4.

It's strange that after deploy (step 2), the Global.asax and *.svc files in the last service become empty.

I checked the source files in PackageTmp, they are not empty.

Does anyone have idea about this?

or does msdeploy have CRC/MD5 check option?

Thank you.

Mikitty