help with astable multivibrator with 555 timer

[fatemehgh]

hi
i've just registered and have a emergency question .
i modeled a astable multivibrator with 555 timer in orcad but it showed this error
convergence problem in bias point calculation, then i enabled skip the initial tran... but now i see this error!"There are no data values in section #1 ignoring this section"
and here is my schematics'
looking forward for your answer.
Thnx.

 

[BradtheRad]

Your schematic has a resistor on the output pin 3 which appears to go to ground...

However there is a red dot over the ground symbol. I think this is where the error is. Notice the other ground icons have no red dot.

I wonder if you ran the resistor and ground together, such that the ends appear to be connected...

Whereas the simulator does not recognize it as such?