Serial port install problem


2020-04-15T08:59:58.980Z Install : node-red-node-serialport 0.10.1

2020-04-15T08:59:59.018Z npm.cmd install --no-audit --no-update-notifier --save --save-prefix="~" --production node-red-node-serialport@0.10.1
2020-04-15T09:00:09.260Z [err] npm
2020-04-15T09:00:09.260Z [err] ERR! Unexpected end of JSON input while parsing near '...TlDXbBxd3yyzp1XKWDzE+'
2020-04-15T09:00:09.291Z [err]
2020-04-15T09:00:09.291Z [err] npm ERR! A complete log of this run can be found in:
2020-04-15T09:00:09.291Z [err] npm ERR! C:\Users\User\AppData\Roaming\npm-cache_logs\2020-04-15T09_00_09_261Z-debug.log
2020-04-15T09:00:09.307Z rc=1

Could you run the install from the command line and post the result please. So go to your node-red folder (wherever that is on Windows, where your flows file is) and run
npm install node-red-node-serialport

npm WARN saveError ENOENT: no such file or directory, open 'C:\Users\User\package.json'
npm notice created a lockfile as package-lock.json. You should commit this file.
npm WARN enoent ENOENT: no such file or directory, open 'C:\Users\User\package.json'
npm WARN User No description
npm WARN User No repository field.
npm WARN User No README data
npm WARN User No license field.
npm WARN optional SKIPPING OPTIONAL DEPENDENCY: bcrypt@3.0.6 (node_modules\bcrypt):
npm WARN optional SKIPPING OPTIONAL DEPENDENCY: bcrypt@3.0.6 install: node-pre-gyp install --fallback-to-build
npm WARN optional SKIPPING OPTIONAL DEPENDENCY: Exit status 1

Do that and try again.
If you don't know where that is then look at the node red startup log. It is where the flows file is.

C:\Users\User.node-red>npm install node-red-node-serialport
npm ERR! Unexpected end of JSON input while parsing near '...TlDXbBxd3yyzp1XKWDzE+'

npm ERR! A complete log of this run can be found in:
npm ERR! C:\Users\User\AppData\Roaming\npm-cache_logs\2020-04-15T17_32_31_971Z-debug.log

That's interesting, that looks as if it might be another npm cache corruption, if so that is the second today and I can't remember if I have ever seen that before, certainly not for a long time. This fixed it for the other instance.

npm cache clean --force

thnx for helping me

I wonder whether the npm repository had a hiccup and was serving out garbage for a while. Otherwise it is a remarkable coincidence that two users independently get garbage in the npm cache on the same day.