We did a quick test and found no issues on MC95 Imager.  We were able to set the aim type to continuous mode and read barcodes.  No exceptions raised. What BSP do you have on MC95?  You have to make sure the reader is enabled before attemtping to set configuations.

You're right, on an MC95 it works. I must have made another mistake on my first check. However, still the value AIM_TYPE_READ_CONTINUOUS doesn't work neither on an MT2090 nor on an MC3090 with imager. If it's not supported on that device, is there a faster way than using AIM_TYPE_TRIGGERED and repeated SoftTrigger = true when I want to scan multiple barcodes on a sheet (serial numbers)? Whatz is the recommended technique?

The continuous read is a fairly new feature and was not available on older devices such as MC3090.  I am in MCD and do not know much about the ADC product MT2090.  Using a combination soft-trigger and trigger notifications, you will be able to accomplish what you trying to do.  I do not believe the performance will be much worse than the continuous mode.  Contact me if you need help. On newer devices such as MC9500, there are better options such as continuous scanning and buffered scanning.