Problem:

Drag and Drop of host VSAM file causes error MFDAS06 Call to module DFCONV failed Unable to convert VSAM/QSAM file

VSAM dataset information shows up as

    Minimum record length 32896

    Maximum record length 1077952576

    Key position 16448

    Key length 16448

Resolution:

This error is caused because the dataset is a host IAM dataset.

Mainframe Access does not support this directly, but IAM files can be downloaded via Drag & Drop if one right-clicks on the host dataset and selects VSAM and then the VSAM type (KSDS, RRDS, ESDS). Since Mainframe Access will be using standard calls into the host Access Method Services, the call to IAM will be resolved and it will return the file in an expected format. The file can then be downloaded without any further action.  This is because the file is not really a VSAM dataset, but an IAM one from Innovation Access Method.    see http://www.fdr.com/iam.cfm

Although these types of datasets are not supported by Mainframe Access for Drag & Drop,  Data Connect can support them because the call into the IBM Access Methods get intercepted by IAM and they appear as VSAM datasets to us (and everybody else).