diff --git a/src/MadsMonteCarlo.jl b/src/MadsMonteCarlo.jl
index 50e9c453..10bc2aec 100644
--- a/src/MadsMonteCarlo.jl
+++ b/src/MadsMonteCarlo.jl
@@ -24,13 +24,13 @@ end
 function loadecmeeresults(madsdata::AbstractDict, filename::AbstractString)
 	if isfile(filename)
 		@info("Load AffineInvariantMCMC results from $(filename) ...")
-		if Mads.jld2haskey(filename, ["chain", "llhoods"]; quiet=false)
+		if !Mads.jld2haskey(filename, "chain", "llhoods"; quiet=false)
 			@warn("$(filename) does not contain AffineInvariantMCMC results!")
 			return nothing, nothing, nothing
 		end
 		chain, llhoods, params, obs = JLD2.load(filename, "chain",  "llhoods", "params", "obs")
 		@info("AffineInvariantMCMC results loaded: number of parameters = $(size(chain, 1)); number of realizations = $(size(chain, 2))")
-		if Mads.jld2haskey(filename, ["observations", "params", "obs"]; quiet=false)
+		if !Mads.jld2haskey(filename, "observations", "params", "obs"; quiet=false)
 			@warn("$(filename) does not contain AffineInvariantMCMC observation results!")
 			return chain, llhoods, nothing
 		end
@@ -87,14 +87,11 @@ function emceesampling(madsdata::AbstractDict; filename::AbstractString="", load
 				@warn("No preexisting data to load! AffineInvariantMCMC will be not executed!")
 				return nothing, nothing, nothing
 			end
-		else
+		elseif isnothing(observations)
 			@info("AffineInvariantMCMC preexisting data loaded!")
 			return chain, llhoods, observations
 		end
 	end
-	if numwalkers <= 1
-		numwalkers = 2
-	end
 	Mads.setseed(seed; rng=rng)
 	optparamkeys = getoptparamkeys(madsdata)
 	p0 = Array{Float64}(undef, length(optparamkeys), numwalkers)
@@ -112,7 +109,7 @@ function emceesampling(madsdata::AbstractDict; filename::AbstractString="", load
 			p0[i, j] = pmin[i] + rand(Mads.rng, d) * (pmax[i] - pmin[i])
 		end
 	end
-	chain, llhoods, observations = emceesampling(madsdata, p0; numwalkers=numwalkers, seed=seed, rng=rng, kw...)
+	chain, llhoods, observations = emceesampling(madsdata, p0; filename=filename, numwalkers=numwalkers, seed=seed, rng=rng, kw...)
 	return chain, llhoods, observations
 end
 
@@ -149,14 +146,8 @@ function emceesampling(madsdata::AbstractDict, p0::AbstractMatrix; filename::Abs
 	if save && filename != ""
 		JLD2.save(filename, "chain", chain, "llhoods", llhoods, "params", Mads.getoptparamkeys(madsdata), "obs", Mads.getobskeys(madsdata))
 	end
-	local observations
-	try
-		observations = Mads.forward(madsdata, permutedims(chain))
-	catch e
-		@warn("AffineInvariantMCMC observations cannot be computed!")
-		observations = nothing
-	end
-	if !isnothing(observations) && save && filename != ""
+	observations = Mads.forward(madsdata, permutedims(chain))
+	if save && filename != ""
 		Mads.jld2append(filename, "observations", observations)
 	end
 	return chain, llhoods, observations