As of early November, MMEX is not able to update stock investment as the following URL doesn't work anymore:
http://download.finance.yahoo.com
This is caused by Yahoo disabling this service which was used by many apps, websites, APIs etc. including Yahoo itself (https://finance.yahoo.com), so some of their own services have stopped working as they directly depend on above service.
The above URL returns the following:
"It has come to our attention that this service is being used in violation of the Yahoo Terms of Service. As such, the service is being discontinued. For all future markets and equities data research, please refer to finance.yahoo.com."
It remains a mystery what violation of terms of service caused Verizon to shut down this service.
There are many discussions over the internet about outraged users that have their apps, calculations, spreadsheets etc. deeply tied to this service and have invested years in something that doesn't work anymore without any early notice/announcement

Here's one of many discussions:
https://forums.yahoo.net/t5/Yahoo-Finan ... d-p/387096
Poll to put shutdown service back online:
https://yahoo.uservoice.com/forums/3829 ... bring-back
What this means for MMEX is that we need an alternate service to handle stocks assuming Verizon won't change their mind and turning back on this service.
I've read some users claiming that MorningStar has a service that can be used as a replacement, but don't know the URL and if it would be fully compatible with MMEX.
Any additional info is welcome.