For those meters with dates in last year, it is possible that they were never installed. For those cases, it is necessary to go back to the original commissioning sheets, and see if they were really installed.
I see that for ones you mention that only read up to 11th of April, the modem for Rep place was still in CSD mode (for which we schedule no automatic reads on your server); instead of GPRS. So this is something to check when it says 'Partial Read' on the Problem Meter List.
I now switched this modem to be on Automatic mode again. Hopefully they will come in again before tomorrow.
As for the rest:
I've looked at a number of these meters, on the bulk view (Tools->Problem Meter List); as well as the per meter view (View->Meter Read Log).
The reason for the meter not calling in is under the Problem column heading for the Problem Meter List, and under the outcome column heading on the Meter Read Log.
Of the remaining ones, it is typically one of the following:

1. that it cannot connect (Could not connect); in which case the modem is off or the aerial stolen or aerial has been moved or doesn't have signal or airtime or SIM card is a problem,
   (typically over here, it would be all meters at this connection/site that is giving this same error)
   
2. or that the meter doesn't answer back at all (Could not find meter at address; Communication error, no answer back); in which case it could be the airtime, or the communication cable between the modem and meter not plugged in or not making contact
   (typically over here, it would be a clump of meters at this connection/site that is giving this same error, although it could also be just one or two that is in close proximity of each other)
   
3. or a bad connection (Communication error); in which case retrying the meter could help, but the communication cables really need to be looked at and any loose connections fixed.
   (this could typically affect a large part of the site, even all of a site, or just one or two meters that are perhaps far away from the others and not hearing the signal clearly)
   
   
   

For all of the above, it is usually a number of meters at a site that is giving problems, and it is possible that a knowledgeable person who is not an electrician can fix the problem by either going to the modem for point 1, or the modem or the relevant meters for point 2, or the meters for point 3, and check the communication cables.
For those problems where it is just one meter, or where the data coming back is strange, the chances are higher that it is an electrical fault, and you would send out an Electrician to look at the meter itself, although it has happened sometimes with a number of meters in proximity to each other to break at the same time, probably due to a power surge or some such (this is very rare).
In other words, I'm of the opinion that most of your problems should be solvable by the center managers (non electricians). If you have modem or communication cable problems and your center managers doesn't know how to fix it, can I suggest you organize with us to send someone to go WITH YOUR CENTER MANAGER, and look at any problem that might be found there, so that we can do any necessary skills transfer. We would be charging for a site visit, but we'll at the same time be training your center manager, to be able to solve such problems in future.
We're also available to offer free telephonic technical support to you or a site manager about a specific problem, e.g. when he is on site and wanting to fix it, as long as he has come for training of at least a day.

Before I sent the electrician out to site I did check to see the “problem” as per your post you have sent me. “or that the meter doesn't answer back at all (Could not find meter at address; Communication error, no answer back); in which case it could be the airtime, or the communication cable between the modem and meter not plugged in or not making contact”.

1. The meter does have air time (I check all the meters on a weekly basis and the one’s which have less than R50.00, I “top-up”); so it can’t be that it does not have air time.
2. I then sent Presto out to check the communication cable to see if it was plugged in and making contact and that is when they came back to me to say that everything was in order and that the meter is in working order.

What else can be wrong if not the above, as I still can’t pull provisional bills for these meters.

I see there are 5 meters at this small center, all of which are not calling in. (They are all connected to the same modem)
Furthermore, I checked the 'Last Read Up to Date & Time' , to see when they went offline.
It appears they went offline in 2 'groups':
From that it can be seen that something happened just after 2011-12-31 19:30 to take 6390872 (Shop 4) and 63900852 (Shop 3) offline - at the same time.
The second event happened just after 2012-03-01 02:00, and it took down the remaining 3 meters - at the same time.
The fact that the meters didn't fail one at a time, implies that it is probably a cable problem. The fact that Shop 4 and Shop 3 failed first, probably means that they share a cable from the modem, that leads to just them, or if all of the meters are daisy chained together, that they are on the end of the chain, and that the specific cable that failed first was the cable towards the modem from Shop3/4.
Then, on the First of March, something happened on site to make the cable leading from the modem to the first meter to fail.
Since all of them are now failing - to make sure it is not a modem problem - I went to look in the Meter Read Logs of one of the meters. I saw that the problem said 'Could not find meter at address'. This means it is probably not a modem problem, since it at least looked for the meter. If the modem didn't connect at all, the problem would have been something like 'Cannot Connect'. We have to connect the modem to the server before we can talk to the meter on the other side of the modem, so we know the modem appears to be working - as you've said, it has airtime.
Therefore, it appears that the problem is a cable problem. The fact that Presto says it appears correct means nothing. The cable could be pulled out half a millimeter - invisible to the human eye - and still be electrically disconnected. The cable could have been bent out of shape by a shop-fitter and the copper broken off inside the plastic where no-one can see.
The best is if Presto pulls out the cable and plugs in the cable again, and hear the sharp 'click' sound when it does so. Have they done that? Also check the point where the cable plugs into the modem: plug it out and plug it in again. Check the cable over its whole length for breaks or abuse of any kind. If they have fresh cables available that they have verified works before going to site, try to substitute that cable temporarily, and see if it works.
It is important that the technician that is on site must log on to Plug and Play Scada whilst on site, as we've teach in our courses, and try the communication there and then. This is part of the troubleshooting process. Just to look at the cables and see if they appear fine at first glance is not good enough.
The correct process is to first leave only the first meter plugged in, while the others are plugged out, and try to read that one meter (that is the simplest configuration: that therefore just checks the 1 cable from the modem to the first meter). If that then works, the other meters must be added bit by bit by plugging in more cables, until it stops working, at which point the electrician has found the cable that is causing the problems.
And are you sure they have not just checked the Electrical cables? They are electricians, so with them you have to be very specific and say they must check the Communication cables.

What else can I do for the below. Presto has been out to site and they say everything is in order, but yet I am receiving errors every morning on Plug and Play Scada.

The fact that Presto says it appears correct means nothing.
Have they connected only the first meter to the modem, and checked, while on site, that pnpscada communicates to the first meter? And if not, have they disconnected and reconnect that cable at both sides, and then checked the communication again, while on site?

If they have not done the above, they have not done enough.
Once they get the first meter working, then they move on to the next one and repeat the process, etc.
We have trained some Presto technicians to read in the meters while on site. This is a mayor innovation of Plug and Play Scada, to get technicians to be more effective. If Presto doesn't have enough trained personnel, (personnel trained on pnpscada); then they must send them to get training. Clearly, the technicians that Presto sent out to site has not been trained, or they have become lazy.