ProjectWise Error 222 - User Can't Open DGN

Two users in ProjectWise cannot open DGN files. They receive Error 222:

When I look at the pwc.log file, it has this entry:

2019-11-18 10:55:24,206 FATAL [0x00001d0c] pwise.dms.workspace - processConfigurationFiles(): Runtime error occured. CsbFileIncluder has failed to get CSB file names for a level.

2019-11-18 10:55:24,206 ERROR [0x00001d0c] pwise.dms.workspace - Failed to compile configuration files. Compilation failed with aaApi error [50164] and error message [(null)].

2019-11-18 10:55:24,207 ERROR [0x00001d0c] pwise.dms.workspace - Failed to create final configuration file.

2019-11-18 10:55:24,207 ERROR [0x00001d0c] pwise.dms.workspace - Configuration file generation for the document [91637, 8] failed.

2019-11-18 10:55:25,324 ERROR [0x00001d0c] pwise.dms - Error 222 "Cannot start application for the specified document. Check your program associations.

Failed to generate managed workspace configuration file.

An exception raised."

I tried logging in with my credentials on the affected PC, but I too received the same error on that PC. I'm wondering what (if anything) on a particular PC would prevent the Configuration Settings Blocks' names from being delivered. The problem sure feels PC specific. 

Of note: this is not on our own PW system, but rather that of another company hosting files for our use.

Any ideas are appreciated!