This will resolve the issue:
KA371087 - BBSA Windows Catalog Update Job error: Could not open the file //[helper_server]/[temp_xxx]//hf7b-decrypted.xml: No such file or directory
seeing that your path in the erorr message does not have any spaces, I'd guess that you will have to follow this KB referenced from the above KB:
KA370265 - BBSA Windows Patch Catalog, Analysis, Hotfixes error: 80004005 Downloaded Cab file '[temp_folder]/hf7b.cab' is not trusted.
I got the same error today trying to update my Windows patch catalog.
After 30 minutes I rerun the catalog update job and it finished succesfully.
I didn't touch any configuration, so no idea what the problem was.
I think the shavlik website from where the xml is downloaded was down for a few moments this morning. I looks to be up and running now.