Can't read sectors via heads map

[d1d]

hello,

i have a st2000dm001 which is not mounting.
so i tried to get the data with the DE.
When i try to build a heads map most of the sectors won't get read but if i click on them it works.
Am i right that this means that the heads are working but don't read properly with the heads map tool.
The Log says:
Search for MCMT RAM FD in RAM........... Error
can someone tell me how to read the sectors ?

best regards

[digitalsupport]

Just to understand
You build headmap and that completes. Then you start imaging the complete drive to destination drive (file, virtual or other) ?
If not reading all sectors you must have some settings in task that tells it not to read.

If possible I prefer to do like this:
Setup a task imaging to network.
Build headmap.
Map metadata depending on FS
Image metadata
Error check metadata
Map needed data and image

During any read operation any error or glitch is noted, heads, LBA error, all that can help to understand whats going on. Info gathered puts together the plan on how to get data in the safest way, LBA ranges, heads to avoid in first run.