我通过Testovertheair这种方式测试iOS程序，但是有时会遇到“无法下载应用程序”的错误，详细信息里只提示“当前无法下载xxx”。对于这种情况，该如何诊断呢？以前遇到过这种问题，比如目标平台的要求设定过高（如iOS5.1但手机只有5.0），或者是简单的网络问题等。补充：部署到自己的服务器上无法下载和安装，但是通过TestFlight可以，所以目前安装包应该没有问题。我还用iPhoneConfigurationUtility看了一下手机的控制台输出，似乎也没有看到什么问题，日志如下（Chrome,iPhone4,iOS5.1.1,越狱版）：''Oct2411:01:38unknownSpringBoard[63]:Posting'com.apple.iokit.hid.displayStatus'notifyState=1Oct2411:01:38unknownUserEventAgent[19]:DEBUG:Changingscreenblankedstate:0Oct2411:01:38unknownSpringBoard[63]:MultitouchHID:detectionmode:255->0(deferringuntilbootloaded)Oct2411:01:38unknownSpringBoard[63]:MultitouchHID:devicebootloadedOct2411:01:38unknownSpringBoard[63]:MultitouchHID:detectionmode:0->0Oct2411:01:38unknownkernel[0]:set_crc_notification_state0Oct2411:01:39unknowncalaccessd[2457]:MS:Notice:Installing:(null)[calaccessd](690.10)Oct2411:01:39unknownsandboxd[2459]:MS:Notice:Installing:(null)[sandboxd](690.10)Oct2411:01:44unknownkernel[0]:launchd[2461]Builtinprofile:container(sandbox)Oct2411:01:44unknownkernel[0]:launchd[2461]Container:/private/var/mobile/Applications/92BF7598-F310-431C-A39B-06C532D6B509[69](sandbox)Oct2411:01:44unknownChrome[2461]:MS:Notice:Installing:com.google.chrome.ios[Chrome](690.10)Oct2411:01:44unknownChrome[2461]:MS:Notice:Loading:/Library/MobileSubstrate/DynamicLibraries/Activator.dylibOct2411:01:44unknownChrome[2461]:MS:Notice:Loading:/Library/MobileSubstrate/DynamicLibraries/SogouInputIPhone4.dylibOct2411:01:45unknownChrome[2461]:MS:Notice:Loading:/Library/MobileSubstrate/DynamicLibraries/libstatusbar.dylibOct2411:01:45unknownChrome[2461]:MS:Notice:Loading:/Library/MobileSubstrate/DynamicLibraries/qihoo.360safesrv.dylibOct2411:01:45unknownChrome[2461]:MS:Notice:Loading:/Library/MobileSubstrate/DynamicLibraries/qihoo.360safesrv1.dylibOct2411:01:46unknownlsd[2462]:MS:Notice:Installing:(null)[lsd](690.10)Oct2411:01:48unknownsecurityd[2464]:MS:Notice:Installing:(null)[securityd](690.10)Oct2411:01:51unknownkeybagd[2466]:MS:Notice:Installing:(null)[keybagd](690.10)Oct2411:02:04unknownitunesstored[2468]:MS:Notice:Installing:com.apple.itunesstored[itunesstored](690.10)Oct2411:02:05unknownwifid[24]:WiFi:[372740525.352535]:ClientitunesstoredisbackgroundapplicationOct2411:02:12unknownsandboxd[2470]:MS:Notice:Installing:(null)[sandboxd](690.10)Oct2411:02:12unknownSpringBoard[63]:couldnotsavethumbnailfordownloadingicon:image=(null)path='/var/mobile/Library/SpringBoard/DownloadingIconImageCache/com.xyz-68B854CC-8188-490F-B895-041B36C63C06'Oct2411:02:12unknowninstalld[2472]:MS:Notice:Installing:(null)[installd](690.10)Oct2411:02:13unknowninstalld[2472]:MS:Notice:Loading:/Library/MobileSubstrate/DynamicLibraries/AppSync.dylibOct2411:02:13unknowninstalld[2472]:AppSyncloadedinto/usr/libexec/installdOct2411:02:13unknownSpringBoard[63]:couldnotsavethumbnailfordownloadingicon:image=(null)path='/var/mobile/Library/SpringBoard/DownloadingIconImageCache/com.xyz-77B038CA-2D1D-4985-928C-2A3271FDA412'Oct2411:02:15unknownSpringBoard[63]:Chrome[2461]:Couldnotstat/private/var/mobile/Applications/92BF7598-F310-431C-A39B-06C532D6B509/tmp/etilqs_Xqc6Sge1rmJT944:NosuchfileordirectoryOct2411:02:15unknownSpringBoard[63]:Chrome[2461]:Couldnotstat/private/var/mobile/Applications/92BF7598-F310-431C-A39B-06C532D6B509/tmp/etilqs_PwcdDzBzGOMgrB8:NosuchfileordirectoryOct2411:02:15unknownSpringBoard[63]:Chrome[2461]:Couldnotstat/private/var/mobile/Applications/92BF7598-F310-431C-A39B-06C532D6B509/tmp/etilqs_cvGlKI57OhTXiVd:NosuchfileordirectoryOct2411:03:25unknownaggregated[62]:PLAggregateStateError:Leavingstatepluggedin_screen_offeventhoughwearenotinit,doingnothingOct2411:03:25unknownaggregated[62]:PLAggregateStateError:Leavingstatepluggedin_chargingeventhoughwearenotinit,doingnothingOct2411:03:25unknownaggregated[62]:PLAggregateStateError:Leavingstateunplugged_screen_offeventhoughwearenotinit,doingnothingOct2411:03:25unknownUserEventAgent[19]:DEBUG:Changingpoweredstate:0Oct2411:03:25unknownkernel[0]:AppleD1815PMUPowerSource:AppleUSBCableDetect0Oct2411:03:25unknownkernel[0]:AppleSynopsysOTGDevice::handleUSBCableDisconnectOct2411:03:27unknownaggregated[62]:PLAggregateStateError:Leavingstateunplugged_asleepeventhoughwearenotinit,doingnothingOct2411:03:27unknownaggregated[62]:PLAggregateStateError:Leavingstateunplugged_screen_offeventhoughwearenotinit,doingnothingOct2411:03:27unknownaggregated[62]:PLAggregateStateError:Leavingstatepluggedin_screen_offeventhoughwearenotinit,doingnothingOct2411:03:28unknownUserEventAgent[19]:DEBUG:Changingpoweredstate:1Oct2411:03:28unknownsecurityd[2477]:MS:Notice:Installing:(null)[securityd](690.10)Oct2411:03:28unknownsandboxd[2476]:MS:Notice:Installing:(null)[sandboxd](690.10)Oct2411:03:28unknownkernel[0]:AppleD1815PMUPowerSource:AppleUSBCableDetect1Oct2411:03:28unknownkernel[0]:AppleD1815PMUPowerSource:AppleUSBCableTypeUSBHostOct2411:03:28unknownkernel[0]:AppleSynopsysOTGDevice::handleUSBResetOct2411:03:28unknownkernel[0]:AppleSynopsysOTGDevice::handleUSBResetOct2411:03:28unknownkernel[0]:launchd[2475]Builtinprofile:ptpd(sandbox)Oct2411:03:28unknownptpd[2474]:MS:Notice:Installing:(null)[ptpd](690.10)Oct2411:03:28unknownptpd[2474]:MS:Notice:Loading:/Library/MobileSubstrate/DynamicLibraries/Activator.dylibOct2411:03:29unknownptpd[2474]:MS:Notice:Loading:/Library/MobileSubstrate/DynamicLibraries/SogouInputIPhone4.dylibOct2411:03:29unknownptpd[2474]:MS:Notice:Loading:/Library/MobileSubstrate/DynamicLibraries/libstatusbar.dylibOct2411:03:29unknownptpd[2474]:MS:Notice:Loading:/Library/MobileSubstrate/DynamicLibraries/qihoo.360safesrv.dylibOct2411:03:29unknownptpd[2474]:MS:Notice:Loading:/Library/MobileSubstrate/DynamicLibraries/qihoo.360safesrv1.dylibOct2411:03:29unknownptpd[2474]:PTPinterfacehasbeenactivatedathighspeed.Oct2411:03:29unknownkernel[0]:launchd[2474]Builtinprofile:ptpd(sandbox)Oct2411:03:30unknownlockdownd[37]:libMobileGestaltcopyMobileEquipmentIdentifier:NoMEIDinCTmobileequipmentinfodictionary-{type=mutabledict,count=5,entries=>1:{contents="kCTMobileEquipmentInfoCurrentSubscriberId"}={contents="460012300660487"}2:{contents="kCTMobileEquipmentInfoCurrentMobileId"}={contents="013130002556488"}4:{contents="kCTMobileEquipmentInfoICCID"}={contents="89860111608311072596"}11:{contents="kCTMobileEquipmentInfoIMEI"}={contents="013130002556488"}12:{contents="kCTMobileEquipmentInfoIMSI"}={contents="460012300660487"}}Oct2411:03:30unknownlockdownd[37]:00381000copy_meid:MobileGestaltfailedtoprovideanMEIDbutreturnednoerror(?)Oct2411:03:30unknowninstalld[2484]:MS:Notice:Installing:(null)[installd](690.10)Oct2411:03:30unknowninstalld[2484]:MS:Notice:Loading:/Library/MobileSubstrate/DynamicLibraries/AppSync.dylibOct2411:03:30unknowninstalld[2484]:AppSyncloadedinto/usr/libexec/installdOct2411:03:31unknownmc_mobile_tunnel[2487]:(Note)MC:mc_mobile_tunnelstarting.Oct2411:03:31unknownmc_mobile_tunnel[2487]:(Note)MC:mc_mobile_tunnelshuttingdown.Oct2411:03:31unknownmc_mobile_tunnel[2488]:(Note)MC:mc_mobile_tunnelstarting.Oct2411:03:31unknownmc_mobile_tunnel[2488]:(Note)MC:mc_mobile_tunnelshuttingdown.Oct2411:03:31unknownlockdownd[37]:00381000set_response_error:handle_start_sessionSessionActiveOct2411:03:35Waynes-iPhonemc_mobile_tunnel[2490]:(Note)MC:mc_mobile_tunnelstarting.Oct2411:03:35Waynes-iPhonemc_mobile_tunnel[2490]:(Note)MC:mc_mobile_tunnelshuttingdown.Oct2411:03:57Waynes-iPhoneCommCenter[68]:NomoreassertionsforPDPcontext0.Returningitbacktonormal.Oct2411:03:57Waynes-iPhoneCommCenter[68]:SchedulingPDPteardowntimerfor(372740937.446775)(currenttime==372740637.446801)Oct2411:03:57Waynes-iPhoneCommCenter[68]:Client[com.apple.persistentconnection[apsd,61]]istellingPDPcontext0togoactive.''----------------------------11月1日补充：现在的情形似乎是通过WIFI可以下载成功，但是3G不行。原以为是ipa文件的mime类型设置不正确，导致下载时无法看到大小（也许是因为服务器用了gzip的缘故）？而因为iPhone会限制3G环境下载大文件，如果无法看到大小，那么下载了一定时间，或者一定大小后还没完成就放弃了。后来将mime改成application/octet-stream用浏览器下载可以看到大小和进度了（WIFI下载也是），但是。。。3G环境下载还是失败。ipa文件大小只有3.5m左右。