"Multimeter": do you mean an analog "VOM" or a modern digital "DMM"?
The reason for that question is how much current you are pulling through the 1 megohm resistor from +4.5 V.
Unless your opamp is blown, or you have an undocumented short circuit, or you have mislabeled the pins in your diagram (inverting the power connections), you should have very close to +4.5 V at that junction, assuming you have +4.5 V at the voltage divider connected to the top end of the 1 megohm resistor R1. Check that node (junction of R7 and R8) first, then disconnect the opamp and see if the +4.5 V reappears.
A typical DMM has an input resistance on DC of 10 megohms, but some cheap ones have only 1 megohm input resistance. Assuming 10 meg, you have a Thevenin equivalent of +4.5 V in series with 1.5 megohm driving the voltmeter, so the theoretical voltage is about 3.9 V with no load besides the voltmeter. However, if a polarized C6 is in backwards, it will short out the +4.5 V.