CVS Health has expanded Curbside pickup to 4,000 stores, including several large markets, but the program was suspended when too much traffic overwhelmed the mobile app.
The program had been tested in several markets and was set to launch on Thursday in Boston, Chicago, Dallas and Seattle. But too many users overwhelmed the system and it was shut down completely Wednesday afternoon, according to The Boston Globe.
Users in Chicago found that the app failed to load and prompted visitors to "please check back later."
CVS has partnered with Curbside and in April said it was investing in the business for its CVS Express program that lets shoppers make in-app nonprescription purchases and pick them up at a designated parking spot.
The program was available at that time in San Francisco, Atlanta, and Charlotte, North Carolina.
CVS is the second national retailer to invest in a third-party mobile fulfillment solution this year. Whole Foods has partnered with and invested in Instacart to provide one-hour delivery for orders from its stores in multiple markets, with an eye to growing the service.
Curbside had been testing a similar program with Target, but in May it discontinued the fledgling partnership to focus on in-store pickup and fulfillment.
CORRECTION: CVS and Curbside experienced heavier than expected traffic and turned off the feature to slow the rollout. According to Curbside, the site did not crash as was originally stated.