Hartford — An effort to upgrade outdated computer systems at the Connecticut Department of Motor Vehicles and make life easier for customers could prove challenging in the early stages, according to state officials.

Longer wait times, confusion, and possible computer glitches are all expected once the improvements take effect on Aug. 18. The DMV is closing all of its offices, except for licensing services, from Aug. 11-15 to prepare for the unveiling. New online services will be available starting Aug. 17.

"We're going to be locked down for that week. We expect a high volume of people coming back after we finally open up on Aug. 18, when we flip the switch on this new system," said DMV Commissioner Andres Ayala Jr. It's unclear whether the heavy volume could last weeks or months, he said.

The department has launched an advertising campaign about the changes and plans to brief state lawmakers and their staff on Thursday.

"Like anything else, it is a new system. There might be some bugs with the system, some glitches, some things that, for whatever reason, are unforeseen on our end or our on our developer's end."

Ayala said DMV is asking customers to be patient and understand that a major new system is being installed.

"This is a huge, huge effort," said Ayala. More than 40 million pieces of data have to be transferred from the old system to the new one, he added.

"We're in 2015. People are going around using their cellphones as a way to transact business — tablets, laptops, PCs," Ayala said. "That didn't exist when our old system was around so those capabilities weren't there."

DMV plans to offer a host of new online services, including improvements to the existing online vehicle registration renewal program and the ability for a customer to check whether they have unpaid property taxes, lack insurance or have delinquent parking violations — all things that hold up a registration renewal and cause repeated trips to the DMV. Licensing services, however, will not be affected.

Connecticut began efforts to modernize its computer system about six years ago. Ayala estimates about $25 million has been spent on the project.

Other states that have attempted to move more services online have faced problems, from backlogs to cost overruns. Ayala contends Connecticut DMV's project leader has been in touch with other states, learning what to do and not do when rolling out a modernization effort, particularly a registration-related one.

Ayala said Connecticut's DMV learned that the states that focused on training staff on the new system and asked workers to practice have been most successful. In Connecticut, branches closed for a week over February and March for training on the upgrades.

In the meantime, to help ease the anticipated effects of the shutdown, expiration dates of all driver's licenses, ID cards and vehicle registrations will be extended through Oct. 10, beginning Aug. 11. That means renewals can be done for nearly two months without a late fee and motorists shouldn't feel the need to visit the DMV immediately after the branches reopen, Ayala said.

DMV's upgrade rollout comes amid concerns about a backlog in scheduling tests for driving licenses and permits. Part of that backlog has been due to a new state law allowing immigrants who do not have legal status in Connecticut to obtain drive-only licenses and permits. DMV has since readjusted the schedule for obtaining knowledge and road tests and Ayala said he doesn't foresee that situation exacerbating any issues with the computer upgrade.

Last week, Gov. Dannel P. Malloy said it's not surprising that allowing a new group of people to obtain driver's licenses would affect the system.

"I think this is one of those things that you simply have to power through. You've got to get the backlog taken care of and you've got to do it as rapidly as you can," he said. "And that just happens to be coinciding with the implementation of new technology."