Host repeats a task 3 times, error E4021 is then entered. 
If the Memoskop C / CE 100 / C-MOD / C-SUB / C-SUB &MOD was replaced, try "Erase Harddisk". 
(Memoskop, Technical setup, menu "Diagnostics" - "Erase Harddisk") 
Note: Ask your customer before you start erasing ! 
All images will be lost ! 
Check for additional error messages E2006 and E4024. 
Possibly Memoskop defective. 

Error E2005 Videomed DC, ser. receive line error 

Possible trouble: The receive line has a constant level. 

Possible help: Check receive line between D1 and Videomed DC. 
Check service switches on D4. 
In normal use, all switches s1 to S8 should be set to OFF. 
Possibly D4 or D1 defective. 

Error E5006 Gen. tried X-Ray on without SS relais 

Possible trouble: Generator attempts radiation with SS relay switched off. 

Possible help: D1, switch S2 in wrong position. 
D1 defective.

Thank You