Thanks Tim.
I have checked now that the behavior of the "bug" depends on the machine the previous .nb is run on.
-On my home machine/license (10.0.1 in Win 8.1, 64 bits) the "bug" does appear as in the notebook provided:
the last outputs are then
Out[8]=sp1900sc[[1]]
Out[9]=Symbol
-On my office machine/license (10.0.1 in Win 7, 32 bits) the "bug" does not appear, the last outputs are correctly
Out[8]=1
Out[9]=8000
I really do not understand why the same program behaves differently on different machines.
Perhaps it is a function of the number of bits of the operating system, but Tim reports that his
Win 7 OS has 64 bits as well...
Or perhaps the difference is on Win 7 / Win 8.1...
What a mystery...
Best,