DataGridview Column DataType problem Object/String

[Toxo]

Hello,
I'm trying to insert Data into a Cell of a DataGridview and have some problems at the following point.

std::bitset<8> bs ((long)trackBar2->Value);
std::string bss = bs.to_string();

dataGridView1->Rows[i-1]->Cells[1]->Value= bss;

leads to error: Cant convert String to Object.

dataGridView1->Rows[i-1]->Cells[1]->Value= "0101010101010";

Is working fine. Is anyone able to tell me what i did wrong?

Thank you