Mail in Mavericks repeatedly quits

Question

Hey Apple Community! Just solved a problem I have been wrestling with for a couple weeks now. Thought I would post cuz I'm sure I must not be the only one having these issues. This is what happened:
1. Upgraded my MacBook Pro to Mavericks.
2. Tried to open MacMail Ap - would crash repeatedly in a half a second before you could even view a message.
3. Finally did the command/R/restart clean install on the OS, after reading a thread saying this was the only way to fix mail.
4. This did not fix it - same result.
5. Read some more support threads, talked to my Apple Genius daughter who had me diagnose it thru Console. Got the drift that Gmail might be the culprit.
(Console said:
"Application Specific Information:
*** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[MFGmailLabelStore setUid:forMessageWithTemporaryUid:]: unrecognized selector sent to instance 0x60000018b7a0'
abort() called
terminating with uncaught exception of type NSException")
6. By reading even more threads figured out how to disable Gmail account thru SystemPrefs/InternetAccounts, then disable & delete the Gmail Account
7. After doing this, MacMail Ap opened without problems, and I was able to access my .mac/.me/.icloud account(s), without issues.
8. Tried to add the Gmail account back in by doing the usual Mail/AddAccount/Google, like always worked in the past for Gamil. Appears to work for a sec, but no Gmail account appears.
9. By reading further threads & support docs, found an update to stablize Gmail in Mavericks. Downloaded & opened it, but it said I was ineligible for this update.(?) Ok Whatever.
10. Read some more threads, found somebody having issues with Gmail on their iPhone (which I am not). Gmail has worked just fine on all my other Apple toys this whole time. Only issue was with the MacBook I upgraded to Mavericks. This person said Google was no longer supporting Gmail. This was news to me.
11. On a whim, tried adding the Gmail account back into the MacMail as an "Other" account, instead of as a "Google" account.
12. This worked. No further issues. Maybe I am the last Mac user to find this out, but maybe not & this helps somebody else. Just sayin.'

Answer 1

Hello everybody,
i've solved the problem. But it doesnt work for all signatures, just for one individual. You have to edit the files for Apple Mail AND Apple Mail on iCloud, else the other file overwrite the other...
1. Go to the following paths (user library):
Apple Mail:
~/Library/Mail/V2/MailData/Signatures/
Apple Mail on iCloud :
~/Library/Mobile Documents/com~apple~mail/Data/MailData/Signatures/
2. When you have located the placeholder .mailsignature  file, drag it on your desktop, and delete the original file in the folder. Open the file on desktop with your html editor. You will see a few metadata lines on the top of the file and some html code below. Replace just the html code with yours. Save the file.
3. Do Step 2 also with the .mailsignature file for iCloud.
4. You have an individual signature for a specific mail acc.
Regards,
Lui