Wifi connection since ios 16.3.1 update

You haven’t actually described your “issue”. Perhaps the following will help you to troubleshoot the problem…

Start with basic WiFi troubleshooting - as detailed here:

If your iPhone, iPad, or iPod touch won’t connect to a Wi-Fi network - Apple Support

Recommended settings for Wi-Fi routers and access points - Apple Support

If your WiFi has been set-up according to Apple’s recommended settings, WiFi and Internet connection difficulties are usually an indication that your device does not have a routable IP Address - your IP Address usually being assigned by DHCP. When this occurs, your iPad may only have a self-assigned link-local IP address that begins 169.254.x.x.

System software updates can, in some circumstances, trigger a problem with the iPad (or iPhone) internal routing table. The causes are many, but are usually attributable to some types of App or associated device configuration.

If you have a VPN App or profiles installed, or a security App such as Norton, these may be interfering with DHCP - and preventing your device from obtaining a valid IP Address for the WiFi network/hotspot to which you are attempting to connect. The resolution is usually simple; if installed, you may only need to temporarily disable or remove the Security App and/or VPN.

DHCP is frequently used to automatically obtain an IP Address. Until your iPad has a valid IP Address to connect to your network, you will not have an internet connection. Disabling or removing VPN and/or the offending security App should allow DHCP to operate normally - allowing connection to your network and the internet.

If this resolves your issue, the VPN and/or security App can be reinstated after the connectivity problem has been resolved.

If you continue to have difficulties and your iPad is running iPadOS, check to see if your iPad is using the new WiFi Private Address feature. This feature is intended to provide additional privacy and security when using “public” (untrusted) WiFi networks.

Settings > WiFi > [Your WiFi Network / SSID] - tap the “i” icon - Private Address

The Private Address feature is largely unnecessary for your home WiFi network; if enabled, Private Addressing can cause issues if specific MAC addresses are expected by your WiFi Router. You may need to disable this feature - and can be enabled or disabled for each individual network.

Use private Wi-Fi addresses in iOS 14, iPadOS 14, and watchOS 7 - Apple Support

I’m delighted to learn that the issue has been fully resolved.

The active VPN can impact the ability of the iPad to obtain an IP Address for the local network. Temporarily disabling the VPN will usually clear the problem.

The same symptoms seem to occur with specific routers, possibly only when ipv6 support is enabled. Setting a manual IP address, subnet mask and router address, and a manual DNS address resolves the problem, but it may not be a reasonable to hope that the majority of users will be able to do that w/o assistance.

Yes, I have a VPN along with the AVG Security software I added for 2 home PC’s and my Android Tablet for work.

I will disable the VPN thanks to your advice.

Will that cure my sms problem of telling me my message(s) weren’t sent? I’ve received those notifications and re-sent messages, only to hear back, “Why did you send it twice?”

TheHoganFamily wrote:

The same symptoms seem to occur with specific routers, possibly only when ipv6 support is enabled. Setting a manual IP address, subnet mask and router address, and a manual DNS address resolves the problem, but it may not be a reasonable to hope that the majority of users will be able to do that w/o assistance.

Yes, manual IP configuration can work-around the problem by removing DHCP from the equation. This doesn’t, of itself, resolve the underlying problem - which the solution documented above is intended to address.

M-vRic44 wrote:

Yes, I have a VPN along with the AVG Security software I added for 2 home PC’s and my Android Tablet for work.

I will disable the VPN thanks to your advice.

Will that cure my sms problem of telling me my message(s) weren’t sent? I’ve received those notifications and re-sent messages, only to hear back, “Why did you send it twice?”

While temporarily disabling the VPN should clear the problem, in some circumstances it may be necessary to remove the offending App - and restart the device. These steps are sometimes required to clean-up the network-stack. Once resolved, the VPN/security App can be reinstalled if required.

Other than DHCP, other network protocols can be similarly impacted. Messaging and/or other services may be similarly affected.