I am having this issue with a 1.5.4 cart on PHP 5.6. I tried this (https://www.zen-cart.com/downloads.php?do=file&id=2035) but there is no such setting under configuration >> my store.

Here is my debug from the currencies update. I also tried updating the files to 1.5.5 as suggested in another thread for the same result.

Code:
currencies.php:
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7922 9.20532512665 4.05311584473e-06 connect(5, {sa_family=AF_INET, sin_port=htons(80), sin_addr=inet_addr("23.1.120.11")}, 16) = -1 EINPROGRESS (Operation now in progress)
7923 9.20532894135 2.86102294922e-06 poll([{fd=5, events=POLLIN|POLLOUT|POLLERR|POLLHUP}], 1, 60000) = 1 ([{fd=5, revents=POLLOUT}])
7924 9.20533204079 4.05311584473e-06 getsockopt(5, SOL_SOCKET, SO_ERROR, [0], [4]) = 0
7925 9.2053360939 4.05311584473e-06 fcntl(5, F_SETFL, O_RDWR) = 0
7926 9.2053399086 2.86102294922e-06 sendto(5, "GET /stats/eurofxref/eurofxref-daily.xml HTTP/1.0\r\n", 51, MSG_DONTWAIT, NULL, 0) = 51
7927 9.20534300804 4.05311584473e-06 sendto(5, "Host: www.ecb.europa.eu\r\n", 25, MSG_DONTWAIT, NULL, 0) = 25
7928 9.20534706116 4.05311584473e-06 sendto(5, "Connection: close\r\n", 19, MSG_DONTWAIT, NULL, 0) = 19
7929 9.25250005722 0.0471498966217 sendto(5, "\r\n", 2, MSG_DONTWAIT, NULL, 0) = 2
7930 9.25253009796 3.31401824951e-05 poll([{fd=5, events=POLLIN|POLLPRI|POLLERR|POLLHUP}], 1, 0) = 0 (Timeout)
7931 9.25254106522 1.00135803223e-05 poll([{fd=5, events=POLLIN|POLLERR|POLLHUP}], 1, 60000) = 1 ([{fd=5, revents=POLLIN}])
7932 9.25255203247 1.19209289551e-05 recvfrom(5, "HTTP/1.0 200 OK\r\nServer: Apache\r\nLast-Modified: Fri, 23 Jun 2017 13:55:14 GMT\r\nETag: \"658-552a0f3517480\"\r\nAccept-Ranges: bytes\r\nContent-Length: 1624\r\nContent-Type: text/xml\r\nDate: Sat, 24 Jun 2017 00:55:27 GMT\r\nConnection: close\r\n\r\n<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n<gesmes:Envelope xmlns:gesmes=\"http://www.gesmes.org/xml/2002-08-01\" xmlns=\"http://www.ecb.int/vocabulary/2002-08-01/eurofxref\">\n\t<gesmes:subject>Reference rates</gesmes:subject>\n\t<gesmes:Sender>\n\t\t<gesmes:name>European Central Bank</gesmes:name>\n\t</gesmes:Sender>\n\t<Cube>\n\t\t<Cube time='2017-06-23'>\n\t\t\t<Cube currency='USD' rate='1.1173'/>\n\t\t\t<Cube currency='JPY' rate='124.36'/>\n\t\t\t<Cube currency='BGN' rate='1.9558'/>\n\t\t\t<Cube currency='CZK' rate='26.297'/>\n\t\t\t<Cube currency='DKK' rate='7.4372'/>\n\t\t\t<Cube currency='GBP' rate='0.87805'/>\n\t\t\t<Cube currency='HUF' rate='309.13'/>\n\t\t\t<Cube currency='PLN' rate='4.2320'/>\n\t\t\t<Cube currency='RON' rate='4.5715'/>\n\t\t\t<Cube currency='SEK' rate='9.7700'/>\n\t\t\t<Cube currency='CHF' rate='1.0851'/>\n\t\t\t<Cube currency='NOK' rate='9.4613'/>\n\t\t\t<Cube currency='HRK' rate='7.4030'/>\n\t\t\t<Cube currency='RUB' rate='66.6677'/>\n\t\t\t<Cube currency='TRY' rate='3.9235'/>\n\t\t\t<Cube currency='AUD' rate='1.4764'/>\n\t\t\t<Cube currency='BRL' rate='3.7293'/>\n\t\t\t<Cube currency='CAD' rate='1.4783'/>\n\t\t\t<Cube currency='CNY' rate='7.6413'/>\n\t\t\t<Cube currency='HKD' rate='8.7147'/>\n\t\t\t<Cube currency='IDR' rate='14865.68'/>\n\t\t\t<Cube currency='ILS' rate='3.9572'/>\n\t\t\t<Cube currency='INR' rate='72.1025'/>\n\t\t\t<Cube currency='KRW' rate='1271.16'/>\n\t\t\t<Cube currency='MXN' rate='20.1620'/>\n\t\t\t<Cube currency='MYR' rate='4.7910'/>\n\t\t\t<Cube currency='NZD' rate='1.5345'/>\n\t\t\t<Cube currency='PHP' rate='56.117'/>\n\t\t\t<Cube currency='SGD' rate='1.5496'/>\n\t\t\t<Cube currency='THB' rate='37.927'/>\n\t\t\t<Cube currency='ZAR' rate='14.4531'/>\n\t\t</Cube>\n\t</Cube>\n</gesmes:Envelope>", 8192, MSG_DONTWAIT, NULL, NULL) = 1856
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We can also successfully directly curl the relevant URLs:
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root@server [/home/xxx/public_html/xxx]# curl -ks http://www.ecb.europa.eu/stats/eurofxref/eurofxref-daily.xml
<?xml version="1.0" encoding="UTF-8"?>
<gesmes:Envelope xmlns:gesmes="http://www.gesmes.org/xml/2002-08-01" xmlns="http://www.ecb.int/vocabulary/2002-08-01/eurofxref">
<gesmes:subject>Reference rates</gesmes:subject>
<gesmes:Sender>
<gesmes:name>European Central Bank</gesmes:name>
</gesmes:Sender>
<Cube>
<Cube time='2017-06-26'>
<Cube currency='USD' rate='1.1187'/>
<Cube currency='JPY' rate='124.93'/>
<Cube currency='BGN' rate='1.9558'/>
<Cube currency='CZK' rate='26.243'/>
<Cube currency='DKK' rate='7.4364'/>
<Cube currency='GBP' rate='0.87830'/>
<Cube currency='HUF' rate='309.48'/>
<Cube currency='PLN' rate='4.2108'/>
<Cube currency='RON' rate='4.5749'/>
<Cube currency='SEK' rate='9.7618'/>
<Cube currency='CHF' rate='1.0881'/>
<Cube currency='NOK' rate='9.4788'/>
<Cube currency='HRK' rate='7.4126'/>
<Cube currency='RUB' rate='66.0390'/>
<Cube currency='TRY' rate='3.9244'/>
<Cube currency='AUD' rate='1.4771'/>
<Cube currency='BRL' rate='3.7259'/>
<Cube currency='CAD' rate='1.4812'/>
<Cube currency='CNY' rate='7.6541'/>
<Cube currency='HKD' rate='8.7254'/>
<Cube currency='IDR' rate='14882.47'/>
<Cube currency='ILS' rate='3.9501'/>
<Cube currency='INR' rate='72.0980'/>
<Cube currency='KRW' rate='1271.44'/>
<Cube currency='MXN' rate='20.0412'/>
<Cube currency='MYR' rate='4.7970'/>
<Cube currency='NZD' rate='1.5371'/>
<Cube currency='PHP' rate='56.151'/>
<Cube currency='SGD' rate='1.5533'/>
<Cube currency='THB' rate='38.008'/>
<Cube currency='ZAR' rate='14.4089'/>
</Cube>
</Cube>
</gesmes:Envelope>