I have a simmilar problem.
When I connect my iPhone, Xcode has a status line saying it is installing the symbols for the Watch.
The text then disappears and my iPhone becomes inaligible for debuging WatchKit extentions due to "lack of symbols"
(iPhone 5s with iOS 9 - Beta 2 , Xcode 7 - Beta 2, Watch OS 2.0 - 13S5255d)
I decided to run Xcode from command line for possible error traces. It seems that my Xcode is unable to download and mount a file called 'Watch1_1_13S5255d.dmg'. First URL returns 404 and the second URL which is done with my (Admin) team accounts fails with 403.
Perhaps you should too open terminal, run
/Applications/Xcode-beta.app/Contents/MacOS/Xcode
then connect your device and see the traces
Below is a trace from my Xcode:
2015-06-24 14:03:47.849 Xcode[28881:241044] Unable to mount DeveloperDiskImage on Doron's Apple Watch
2015-06-24 14:03:51.189 Xcode[28881:241027] Unable to mount DeveloperDiskImage on Doron's Apple Watch
2015-06-24 14:03:54.494 Xcode[28881:241047] DVTDownloadable: Download Failed. Downloadable: https:/devimages.apple.com.edgekey.net/downloads/xcode/dsc/Watch1_1_13S5255d.dmg. Error Domain=DataWritingNSURLConnectionDelegate Code=1 "Failed with HTTP status 404: not found" UserInfo=0x7fe7393ab310 {NSLocalizedDescription=Failed with HTTP status 404: not found, NSHTTPURLResponse=<NSHTTPURLResponse: 0x7fe7397e8a30> { URL: https://devimages.apple.com.edgekey.net/downloads/xcode/dsc/Watch1_1_13S5255d.dmg } { status code: 404, headers {
Connection = "keep-alive";
"Content-Length" = 16;
"Content-Type" = "text/html; charset=iso-8859-1";
Date = "Wed, 24 Jun 2015 11:03:54 GMT";
Server = Apache;
} }}
2015-06-24 14:03:57.675 Xcode[28881:241047] DVTDownloadable: Download Failed. Downloadable: https:/adcdownload.apple.com/Developer_Tools/watchOS_13S5255d/Watch1_1_13S5255d.dmg. Error Domain=DVTDownloadableErrors Code=8 "The operation couldn’t be completed. (DVTDownloadableErrors error 8.)" UserInfo=0x7fe735eba350 {Errors=(
"Error Domain=DataWritingNSURLConnectionDelegate Code=1 \"d****@f********.com.com does not have access to Symbols for watchOS 2.0 (13S5255d).\" UserInfo=0x7fe738a92ac0 {NSRecoveryAttempter=<_DVTErrorRecoveryHandler: 0x7fe7396e4a90>, NSLocalizedRecoverySuggestion=Contact Apple Developer Support to resolve account access issues., NSLocalizedDescription=d****@f********.com.com does not have access to Symbols for watchOS 2.0 (13S5255d)., DVTRecoveryBlockKey=<__NSMallocBlock__: 0x7fe7396f23b0>, NSLocalizedRecoveryOptions=(\n OK,\n \"Contact\\U2026\"\n), NSHTTPURLResponse=<NSHTTPURLResponse: 0x7fe73857a290> { URL: https://adcdownload.apple.com/Developer_Tools/watchOS_13S5255d/Watch1_1_13S5255d.dmg } { status code: 403, headers {\n \"Cache-Control\" = \"max-age=0, no-cache, no-store\";\n Connection = close;\n \"Content-Type\" = \"text/html\";\n Date = \"Wed, 24 Jun 2015 11:03:56 GMT\";\n Expires = \"Wed, 24 Jun 2015 11:03:56 GMT\";\n Pragma = \"no-cache\";\n \"Strict-Transport-Security\" = \"max-age=1500000\";\n \"X-FRAME-OPTIONS\" = DENY;\n} }, NSUnderlyingError=0x7fe73411c080 \"Failed with HTTP status 403: forbidden\"}",
"Error Domain=DataWritingNSURLConnectionDelegate Code=1 \"d*********@g***.com does not have access to Symbols for watchOS 2.0 (13S5255d).\" UserInfo=0x7fe735ad99d0 {NSRecoveryAttempter=<_DVTErrorRecoveryHandler: 0x7fe738ff4730>, NSLocalizedRecoverySuggestion=Contact Apple Developer Support to resolve account access issues., NSLocalizedDescription=d*********@g***.com does not have access to Symbols for watchOS 2.0 (13S5255d)., DVTRecoveryBlockKey=<__NSMallocBlock__: 0x7fe735ff8240>, NSLocalizedRecoveryOptions=(\n OK,\n \"Contact\\U2026\"\n), NSHTTPURLResponse=<NSHTTPURLResponse: 0x7fe73240d6a0> { URL: https://adcdownload.apple.com/Developer_Tools/watchOS_13S5255d/Watch1_1_13S5255d.dmg } { status code: 403, headers {\n \"Cache-Control\" = \"max-age=0, no-cache, no-store\";\n Connection = close;\n \"Content-Type\" = \"text/html\";\n Date = \"Wed, 24 Jun 2015 11:03:57 GMT\";\n Expires = \"Wed, 24 Jun 2015 11:03:57 GMT\";\n Pragma = \"no-cache\";\n \"Strict-Transport-Security\" = \"max-age=1500000\";\n \"X-FRAME-OPTIONS\" = DENY;\n} }, NSUnderlyingError=0x7fe73262fc90 \"Failed with HTTP status 403: forbidden\"}"
)}
2015-06-24 14:04:00.324 Xcode[28881:241430] DVTDownloadable: Download Failed. Downloadable: http:/adcdownload.apple.com/Developer_Tools/watchOS_13S5255d/Watch1_1_13S5255d.dmg. Error Domain=DVTDownloadableErrors Code=8 "The operation couldn’t be completed. (DVTDownloadableErrors error 8.)" UserInfo=0x7fe738f43680 {Errors=(
"Error Domain=DataWritingNSURLConnectionDelegate Code=1 \"d****@f********.com.com does not have access to Symbols for watchOS 2.0 (13S5255d).\" UserInfo=0x7fe735fecf60 {NSRecoveryAttempter=<_DVTErrorRecoveryHandler: 0x7fe732417620>, NSLocalizedRecoverySuggestion=Contact Apple Developer Support to resolve account access issues., NSLocalizedDescription=d****@f********.com.com does not have access to Symbols for watchOS 2.0 (13S5255d)., DVTRecoveryBlockKey=<__NSMallocBlock__: 0x7fe739691350>, NSLocalizedRecoveryOptions=(\n OK,\n \"Contact\\U2026\"\n), NSHTTPURLResponse=<NSHTTPURLResponse: 0x7fe73924f340> { URL: https://adcdownload.apple.com/Developer_Tools/watchOS_13S5255d/Watch1_1_13S5255d.dmg } { status code: 403, headers {\n \"Cache-Control\" = \"max-age=0, no-cache, no-store\";\n Connection = close;\n \"Content-Type\" = \"text/html\";\n Date = \"Wed, 24 Jun 2015 11:03:59 GMT\";\n Expires = \"Wed, 24 Jun 2015 11:03:59 GMT\";\n Pragma = \"no-cache\";\n \"Strict-Transport-Security\" = \"max-age=1500000\";\n \"X-FRAME-OPTIONS\" = DENY;\n} }, NSUnderlyingError=0x7fe739183c40 \"Failed with HTTP status 403: forbidden\"}",
"Error Domain=DataWritingNSURLConnectionDelegate Code=1 \"d*********@g***.com does not have access to Symbols for watchOS 2.0 (13S5255d).\" UserInfo=0x7fe73445bd50 {NSRecoveryAttempter=<_DVTErrorRecoveryHandler: 0x7fe738506890>, NSLocalizedRecoverySuggestion=Contact Apple Developer Support to resolve account access issues., NSLocalizedDescription=d*********@g***.com does not have access to Symbols for watchOS 2.0 (13S5255d)., DVTRecoveryBlockKey=<__NSMallocBlock__: 0x7fe73859c3b0>, NSLocalizedRecoveryOptions=(\n OK,\n \"Contact\\U2026\"\n), NSHTTPURLResponse=<NSHTTPURLResponse: 0x7fe7390b71b0> { URL: https://adcdownload.apple.com/Developer_Tools/watchOS_13S5255d/Watch1_1_13S5255d.dmg } { status code: 403, headers {\n \"Cache-Control\" = \"max-age=0, no-cache, no-store\";\n Connection = close;\n \"Content-Type\" = \"text/html\";\n Date = \"Wed, 24 Jun 2015 11:04:00 GMT\";\n Expires = \"Wed, 24 Jun 2015 11:04:00 GMT\";\n Pragma = \"no-cache\";\n \"Strict-Transport-Security\" = \"max-age=1500000\";\n \"X-FRAME-OPTIONS\" = DENY;\n} }, NSUnderlyingError=0x7fe73853f660 \"Failed with HTTP status 403: forbidden\"}"
)}