Edit: One of my bam files has size 0 on disk!

I get the following error when I call summarizeOverlpas:

Error in names(res) <- nms :
  'names' attribute [15] must be the same length as the vector [2]
Calls: summarizeOverlaps ... .dispatchBamFiles -> bplapply -> bplapply -> bplapply -> bplapply
In addition: Warning message:
stop worker failed:
  'clear_cluster' receive data failed:
  reached elapsed time limit
Execution halted
Warning messages:
1: In doTryCatch(return(expr), name, parentenv, handler) :
  [bam_header_read] EOF marker is absent. The input is probably truncated.
2: In doTryCatch(return(expr), name, parentenv, handler) :
  [bam_header_read] invalid BAM binary header (this is not a BAM file).
... >Error in serialize(data, node
$con, xdr = FALSE) : ignoring SIGPIPE signal
Calls: bpstart ... .send_VALUE -> <Anonymous> -> sendData.SOCK0node -> serialize
Error in serialize(data, node$con) : ignoring SIGPIPE signal
Calls: local ... .send_VALUE -> <Anonymous> -> sendData.SOCKnode -> serialize
Execution halted

The code that I use is the following:

library(Rsamtools)
library(GenomicAlignments)
library(TxDb.Celegans.UCSC.ce10.ensGene)
library(BSgenome.Celegans.UCSC.ce10)

# read in paths of bam files
tt <- read.csv(file.path(getwd(),'data', 'samplesBam.txt'), header = T, sep='\t')
bfl <- BamFileList(as.character(tt$FileName), yieldSize=1e6)

names(bfl) <- tt$SampleName

query <- genes(TxDb.Celegans.UCSC.ce10.ensGene,
               filter=list("tx_chrom" = seqnames(BSgenome.Celegans.UCSC.ce10)[1:6]))

library(BiocParallel)
multicoreParam  <-  SnowParam(workers = 8)
register(multicoreParam)
bpisup()
bpstart()
registered()

so <- summarizeOverlaps(features = query,
                        reads = bfl,
                        ignore.strand = F,
                        singleEnd = T,
                        count.mapped.reads=T)