Slackel repos are on sourceforge.net which sometimes has problems or you were tried to download when an upload was happened.
There is no problem here.
So please try again.
Also what version of slapt-get do you have? slapt-get-0.10.2t-x86_64-8dj ? This is the latest.

Apologies for the long delay ...

This has been going on for about 10 days.

I run a:
sudo slapt-get -u

and get:

sudo slapt-get -u
Password:
Retrieving package data [http://www.slackel.gr/repo/x86_64/slackware-current/]...Done
Retrieving patch list [http://www.slackel.gr/repo/x86_64/slackware-current/]... Done
Retrieving ...

I've had this problem for almost 2 weeks now, and I've tried 3 times during this period to upgrade the system. The upgrade will start and a few of the early packages get installed. Then it hits gimp, encounters this error, and the rest of the packages can't be updated.

This is the error message ...

I have an issue upgrading aaa_base again.

Initially I forgot about this post and did a collective:

sudo slapt-get -i aaa_base glibc glibc-i18n glibc-zoneinfo kernel-firmware kernel-headers kernel-huge kernel-modules kernel-source...

1/9 Get http://slackware.uk/slackware/slackware64-current/ aaa ...

I tried reinstalling:

$ sudo slapt-get -i --reinstall vlc
Reading Package Lists...Done
The following packages will be reinstalled:
vlc
0 upgraded, 1 reinstalled, 0 newly installed, 0 to remove, 0 not upgraded.
Need to get 0.0kB/22.6MB of archives.
After unpacking 58.6MB disk space will be freed ...

Finally managed to download and install all updates. You're right that it's just an unreliable sourceforge connection, or perhaps they have restrictions when the traffic volume gets high.

I tried adding keys and got:

sudo slapt-get --add-keys
Password:
Retrieving GPG key [http://www.slackel.gr/repo/x86_64/slackware-current/]...Cached
GPG key already present.
Retrieving GPG key [http://www.slackel.gr/repo/x86_64/slackware-current/extra/]...Cached
GPG key already present.
Retrieving ...

I have reinstalled the aaa_base package.

However, when I then followed up with a slapt-get -u and slapt-get --upgrade, I got a "missing md5 checksum" message.

I followed your directions here: http://www.slackel.gr/forum/viewtopic.php?p=1001#p1001

to do a sudo slapt-get --clean

before the update ...

The reinstall aaa_base command gives me:

Get http://slackware.uk/slackware/slackware64-current/ aaa_base 14.2-x86_64-4 [12.0kB]...Done


I assume that means I should

sudo /bin/bash upgradepkg --reinstall /var/slapt-get/slackware64/a/aaa_base-14.2-x86_64-4.txz ?

Instead of sudo /bin/bash ...

Is this to be done before or after I upgrade the rest of the packages that don't get picked up in a normal upgrade, ie, the kernel and glibc stuff?