Players worldwide had technical problems related to the mandatory use of a network connection to play and save game data. These issues included network outages, problems with saving progress and difficulty connecting to the game's servers. As a result, some reviewers were unable to review the game, labeling the launch as a "disaster" and the game as "unplayably broken", urging players to avoid purchasing the game until the issues were resolved.
The server problems and negative feedback led some publications to refer to the launch as "disastrous" and others have compared the launch unfavorably to that of Diablo III, which experienced similar problems when it was first released. The issues caused online retailer Amazon.com to temporarily withdraw the downloadable version of SimCity from its marketplace citing customer complaints.
It was also discovered that there were several issues with the GlassBox engine such as traffic taking the shortest route instead of the route with the most available capacity and Sims not living persistent lives but rather going to the nearest available workplace for work and nearest available house after work.
EA responded to server issues by adding additional servers and developing a server patch that disables "non-critical gameplay features [including] leaderboards, achievements and region filters." On the evening of March 7, Maxis general manager Lucy Bradshaw issued a statement in response to the launch problems, stating that more servers would be added over the weekend, thousands of players were playing and "more than 700,000 cities have been built by our players in just 24 hours". She went on to acknowledge that "many are experiencing server instability" and that "players across Europe and Asia are experiencing the same frustration". She confirmed that the number of servers would be increased stating "We added servers today, and there will be several more added over the weekend."
Senior producer Kip Katsarelis commented that the game servers were constantly at maximum capacity, partly due to the large number of players connected for extended periods of time, which has made it difficult for new users to connect: "We added more servers to accommodate the launch in [Australia, Japan, and Europe]... our plan is to continue to bring more servers online until we have enough to meet the demand, increase player capacity and let more people through the gates and into the game."