When I attempt a stash, it fails with the error below.  I tried updating the embedded Git (per this article https://community.atlassian.com/t5/Sourcetree-questions/Sourcetree-cannot-clone-pull-anymore-sh-exe-stackdump/qaq-p/82962#U909013) and though it finished without error, the version was never updated as displayed.  I tried the update a second time with the same result.  So I downloaded Git to another location and switched SourceTree to System.  That allowed me to actually stash without error, albeit, very slowly.

Error:

git -c diff.mnemonicprefix=false -c core.quotepath=false --no-optional-locks -c credential.helper= -c credential.helper="C:/Users/barnesr/AppData/Local/ATLASS~1/SOURCE~1/GIT_EX~1/GIT-CR~1.EXE" stash save Embedded
1 [main] sh 1880 fork: child 1640 - died waiting for dll loading, errno 11
C:/Users/barnesr/AppData/Local/Atlassian/SourceTree/git_local/mingw32/libexec/git-core\git-stash: fork: retry: Resource temporarily unavailable

1255322 [main] sh 1880 fork: child 19464 - died waiting for dll loading, errno 11
C:/Users/barnesr/AppData/Local/Atlassian/SourceTree/git_local/mingw32/libexec/git-core\git-stash: fork: retry: Resource temporarily unavailable
3519673 [main] sh 1880 fork: child 2420 - died waiting for dll loading, errno 11
C:/Users/barnesr/AppData/Local/Atlassian/SourceTree/git_local/mingw32/libexec/git-core\git-stash: fork: retry: Resource temporarily unavailable
7743623 [main] sh 1880 fork: child 19684 - died waiting for dll loading, errno 11
C:/Users/barnesr/AppData/Local/Atlassian/SourceTree/git_local/mingw32/libexec/git-core\git-stash: fork: retry: Resource temporarily unavailable
15994075 [main] sh 1880 fork: child 15068 - died waiting for dll loading, errno 11
C:/Users/barnesr/AppData/Local/Atlassian/SourceTree/git_local/mingw32/libexec/git-core\git-stash: fork: Resource temporarily unavailable

Completed with errors, see above.