App installation failed: A valid provisioning profile for this executable was not found

This just started happening. I've been building my AIR app using mxmlc from a Flash project for years now, but now I'm getting the error in the title when I try to install the ipa.

I'm installing onto an iPad running iOS 7.0.2 (11A501) from XCode 8.2.1 (8C1002).

I've checked and recreated the certificate for the app, after clearing all other developer certificates from KeyChain.

Here's the log from XCode:

May 23 14:03:24 jwebbs-iPad mobile_installation_proxy[93] <Warning>: LaunchServices: installing app for existing placeholder (null)

May 23 14:03:24 jwebbs-iPad installd[59] <Notice>: 0x343000 handle_install_for_ls: Install of "/var/mobile/Media/PublicStaging/TabletClientTEST.ipa" requested by mobile_installation_proxy

May 23 14:03:24 jwebbs-iPad installd[59] <Notice>: 0x343000 MobileInstallationInstall_Server: Installing app com.xxx.xxx.TabletClient

May 23 14:03:24 jwebbs-iPad installd[59] <Error>: profile not valid: 0xe8008011

May 23 14:03:24 jwebbs-iPad installd[59] <Error>: 0x343000 install_embedded_profile: Could not install embedded profile: 0xe8008011

May 23 14:03:25 jwebbs-iPad securityd[77] <Error>: ocsp response signed by certificate which does not satisfy ocspSigner policy

May 23 14:03:25 jwebbs-iPad installd[59] <Error>: 0x343000 verify_signer_identity: MISValidateSignatureAndCopyInfo failed for /var/tmp/install_staging.cdL7qQ/foo_extracted/Payload/xxx.app/xxx: 0xe8008015

May 23 14:03:25 jwebbs-iPad installd[59] <Error>: 0x343000 do_preflight_verification: Could not verify executable at /var/tmp/install_staging.cdL7qQ/foo_extracted/Payload/xxx.app

May 23 14:03:25 jwebbs-iPad mobile_installation_proxy[93] <Error>: 0x2d7000 MobileInstallationInstallForLaunchServices: failed with -1

May 23 14:03:25 jwebbs-iPad mobile_installation_proxy[93] <Warning>: ERROR: MobileInstallationInstallForLaunchServices returned nil

May 23 14:03:25 jwebbs-iPad mobile_installation_proxy[93] <Error>: 0x2d7000 handle_install: Installation failed: Error Domain=LaunchServicesError Code=0 "The operation couldn’t be completed. (LaunchServicesError error 0.)" UserInfo=0x16e28ae0 {Error=ApplicationVerificationFailed, ErrorDetail=-402620395}

May 23 14:03:25 jwebbs-iPad installd[59] <Error>: 0x343000 install_application: Could not preflight application install

May 23 14:03:25 jwebbs-iPad lockdownd[50] <Notice>: 01996000 set_response_error: handle_get_value GetProhibited

May 23 14:03:25 jwebbs-iPad installd[59] <Error>: 0x343000 handle_install_for_ls: API failed

Any ideas? As I say, this just started happening. I've gone through all the forums and can't find anything that quite matches. I tried changing the KeyChain Certificates options to avoid using OCSP, but that didn't make any difference.