Yum Upgrade Error : GPG key retrieval failed: [Errno 14] curl#37

Following error occurred While upgrading Fedora 19 to Fedora 20 through yum.

Error Message:

Retrieving key from file:///etc/pki/rpm-gpg/RPM-GPG-KEY-fedora-i386
Error: GPG key retrieval failed: [Errno 14] curl#37 – “Couldn’t open file /etc/pki/rpm-gpg/RPM-GPG-KEY-fedora-i386”

Solution:

Install the new Fedora 20 gpg key and upgrade fedora

To Fedora 19 to 20.
#rpm –import /etc/pki/rpm-gpg/RPM-GPG-KEY-fedora-20-$(uname -i)
#yum update

To upgrade Fedora 20 -> Fedora 21 run
#rpm –import /etc/pki/rpm-gpg/RPM-GPG-KEY-fedora-21-$(uname -i)

To upgrade Fedora 21 -> Fedora 22
#rpm –import /etc/pki/rpm-gpg/RPM-GPG-KEY-fedora-22-$(uname -i)

Removed all the old rpms and headers from the yum cache in /var/cache/yum.
After cleaning the cache fedora upgradation started successfully