Moving a client back from the archive area to the active area has always been a sore point in Simon development. Finally, with Version 4, this operation has been made simple. Now, this probably doesn't happen very often, but it can happen and I do get calls on this a few times a year. You can find this tool from the Simon helper as shown below.
Once you open this tool, you will see a list of the clients that you have closed. You simply need to choose the client that you want to reopen from the list and then click on the [Next Screen >>] button.
Once you have move to the next screen you will either be offered to finish the operation, which is quite simple or, in the case shown below where the box has already been rented to another user, you can offer this tardy client a different box. I would say that 95 percent of the time, you will just be able to put the client right back into the same box, but I did want to show you what Simon will do if the client's old box has already been rented.
So, you would simply choose a box that they want instead of their old box. This box will be the same size box that they were in. If they want a different size box, you will have to put them into a box of the same size and then use a different tool that Simon provides to move them to a different box.
Once you select the box to move them to just click on the [Finish] button to reinstate this client into active status.
As you can see from the image above, this client is now in the active area and, when reviewing this clients history, you will see that there is a listing for the move from archive into current, and a listing showing the move from box 322 to box 122.
Hope this helps!