Electrolitic Capacitor of the LNK304 input getting extremely Hot

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I have used the LNK304 to make a small power 24V power supply from the 230VAC (European) grid.
I am using a small RF module (XBee) through a 3v3 linear regulator and the problem is that the electrolytic capacitor 4.7uF/400V that is in the entry of the LNK304 is too hot and there is no ventilation!
I believe that it is because of the RF current spikes that the module may be requesting.
The RF module is not that powerfull, so i think that the LNK304 circuit of the datasheet should be able to drive it.
Supply Voltage 2.1 - 3.6VDC
Transmit Current 35 mA/45 mA boost mode @ 3.3VDC
Receive Current 38 mA / 40 mA boost mode @ 3.3VDC
I tried to use the a full-wave rectifier instead of the half of the example of the datasheet to reduce the ripple but it is still very hot.
I tried to rise the 1mH inductor of the low-voltage side to 4, 5 and 6mH but it is still warm.
I can't make the capacitors bigger because of the space requirements.
Do you have any idea of how to solve the problem?
The original circuit i am using is attached to this post. I'm out of ideas now.
By the way. I need the 24V to drive some relays, but i am not using them right now and they will be turned on just for a few seconds, so i believe it will not be an issue.
Best regards,

How hot is this capacitor getting?
The only way to reduce the temperature is to either reduce the ripple current flowing through the cap. You can do this by using high quality capacitor with low ESR (and higher ripple current rating)