# Error in callback differential equations
**URL:** https://discourse.julialang.org/t/error-in-callback-differential-equations/34781
**Category:** New to Julia
**Tags:** diffeq
**Created:** [February 17, 2020, 10:56pm UTC](https://discourse.julialang.org/t/error-in-callback-differential-equations/34781 "2020-02-17T22:56:17Z")
**Posts on this page:** 3
**Page:** 1
### Author:  [@mleprovost](https://discourse.julialang.org/u/mleprovost)
#### Post date: [February 17, 2020, 10:56pm UTC](https://discourse.julialang.org/t/error-in-callback-differential-equations/34781/1 "2020-02-17T22:56:17Z")
Hello,
I am getting the error `Event repeated at the same time. Please report this error` when I use DifferentialEquations.jl with ContinuousCallback with rootfinder active. Is there a way to go around?
Unfortunately I don’t have a toy problem with this error.
Also is the optional argument ` initialize = (c,u,t,integrator) -> nothing` desactivate the callback at the initial time?
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### Author:  [@ChrisRackauckas](https://discourse.julialang.org/u/ChrisRackauckas)
#### Post date: [February 18, 2020, 1:30am UTC](https://discourse.julialang.org/t/error-in-callback-differential-equations/34781/2 "2020-02-18T01:30:34Z")
> [@mleprovost](#):
>
> Also is the optional argument ` initialize = (c,u,t,integrator) -> nothing` desactivate the callback at the initial time?
yes, that default has the callback not activate at time zero, but of course you can change that.
> [@mleprovost](#):
>
> I am getting the error `Event repeated at the same time. Please report this error` when I use DifferentialEquations.jl with ContinuousCallback with rootfinder active. Is there a way to go around?
> Unfortunately I don’t have a toy problem with this error.
It’s very floating point dependent. When did you last update? We just had some changes that should make this show up much less often (DiffEqBase v6.15.2). @kanav99 may want to look at your MWE if it’s not fixed.
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### Author:  [@kanav99](https://discourse.julialang.org/u/kanav99)
#### Post date: [February 18, 2020, 6:21pm UTC](https://discourse.julialang.org/t/error-in-callback-differential-equations/34781/3 "2020-02-18T18:21:23Z")
Can you check if this error is called at `t = t0`? If thats the case, the issue is known. In any case an example would be very helpful