Error(19496) & Error(19296)

[billmax]

I have an Agilex 7 design I'm building under Quartus Prime Pro 23.2.0 Build 94.  It's not a new design but is in ongoing development, and has been built successfully quite a few times over the last several months.

Lately I have been getting errors in the System tab such as those below during compilation. Quartus help recommends checking file permissions and disk space for those errors but I don't see a problem there as I have well over 100GB free on the drive. Most of the time the compilation finishes anyway but sometimes it terminates abruptly (but well after the errors appear in the System tab) during some fitter stage (usually routing) with no other indication of what caused it to terminate.  There's only one summary error in the Processing tab with no clue as to the root cause.

System tab errors:

Error(19496): Failed to load the 'pre_rtl_constraints_8' database model.
Error(19496): Failed to load the 'pre_mls_constraints_6' database model.
Error(19296): Cannot load partitioned snapshot - ensure the design has been compiled through all earlier stages.

Sometimes there are different database models listed, such as
Error(19496): Failed to load the 'pre_mls_constraints_8' database model.

I have no design partitions defined other than the default root partition.  I have cleaned the project database and rebuilt all qsys and ip with no discernable change in the behavior.

Can anyone shed any light on what else could be causing this, and if the result can be trusted if the constraints aren't properly loaded? Are the database models in question part of my design's qdb, or the device's data in the quartus installation?

I am unable to share this design, unfortunately.

[TingJiangT_Intel]

It seems like the issues are all related to errors in loading the database models. Please check the permissions of the relevant library files and see if they are damaged. You could try reinstalling Quartus to ensure the integrity of the installation files.

[billmax]

Where should these files exist?  I've done a windows explorer search for many permutations of pre_rtl_constraints and don't find them anywhere. Can you be explicit about the folder they should be in?

[TingJiangT_Intel]

I notice another point. Did you restore the project using QAR? Maybe this issue will be caused as the QAR doesn't include all file needed.

If so you may try to choose including all file when generate QAR and restore the project again.

[billmax]

No, quartus archives were not used. I have completely rebuilt the project (multiple times) from the original files (.sv .qsys .ip etc)

It's still not clear to me where these constraint files should be, or how I should go about determining whether they are damaged.

[TingJiangT_Intel]

The best way to check the files is to reinstall Quartus and make sure that access permissions to the installation path are available.

If this issue still exist, you can provide a demo with the same problem for the further investigation as the your original design can't be showed.