TNS:listener could not find available handler for requested type of server

Symptoms
During the import into the Oracle XE database it asks you for a password with the following preceding statement:

ERROR:
ORA-12520: TNS:listener could not find available handler for requested type of
server


Enter user-name:

Cause
As the default the parameter called PROCESSES is specified as 40 or something like that in the Oracle XE Server. This parameter controls the number of processes running simultaneously in one instance on Oracle. Usually it is not enough for large databases with large amount of objects and data.
Solution
Please increase PROCESSES to 100, 200 or even higher.
To increase it, please perform the following steps:
In the System:

set ORACLE_SID=XE

In the SQLPlus:

SQL> alter system set processes=400 scope=spfile;

SQL> shutdown immediate;

SQL> startup;

After that please try rerunning the import.
Please note that the database must be restarted to apply the new value of the processes parameter.