When using the LF 9.1 client, we are seeing the same hanging behavior on multiple machines during scanning with Toshiba e-studio multi-function printers.  During a scan the application hangs, the LFScan.exe and LFTwainClient91.exe processes continue to run in the background.

These printers have a driver called e-Studio Remote Scan driver along with Twain as the scan source.  It appears the printer is physically doing the scan, and sometimes the first page will display but the scan application never finishes and we have to kill the processes.  We don't get any error messages or have not found any errors in logs.

If we go back to the LF 7.2 client, it works just fine.

Has anyone had any experience with using 9.1 with these Toshiba MFP's?  Or similar behavior with the application hanging.