******************* This email originates from outside Imperial. Do not click on links and attachments unless you recognise the sender. If you trust the sender, add them to your safe senders list https://spam.ic.ac.uk/SpamConsole/Senders.aspx to disable email stamping for this address. ******************* Hello, I am solving Linearized Euler Equations using the AcousticSolver on the cluster and I have encountered an issue. I am running initial calculations using a few time steps. The last time-step's field files are provided as an initial condition for the solution sampling phase of calculations. Let's say that the initial run's total simulation time is t_init and the same for next phase of simulations is t_sampling. These are the key-points of my setup : 1. In my initial run's session file the FinTime is set as t_init. For the sampling run, the FinTime is set as t_init + t_sampling 2. I am running the calculations in parallel and hence, the last time-step's folder( which has .chk in it's name) from the initial run is supplied to the InitialConditions field in the session of sampling run. 3. The time step for initial and sampling runs is the same. With the previously outlined setup, I have found that while the sampling phase of simulation run's for the desired total time of t_init + t_sampling , it gives the following error: Fatal : Level 0 assertion violation m_timestep < 0 I have replicated the exact same setup on one of the example cases and it results in the same error. What does this error mean ? Can someone please comment on what could be going wrong ? Regards, Ishan PGR